Do you know the name of the plant species? If you know what it is, I might be able to advise you accordingly.

Post a picture (s) if you don't know the name.

At the rate in which you have said it grows in its natural environment I would say that some thing feeds on it to control its rate of growth. Find out and introduce it to your pond. Beware that just as the introduction of this plant has taken over the pond. The introduction of any new specie may all so. So study the choice carefully before introducing it. Chose one that can be easily eradicated.

Many thanks for the quick response! (Pictures below)

PUBLIC ENEMY NUMBER 1. (name unknown)

From clear water, in only 3-4 months they are 4-6 feet high in a
"jungle" mass, a giant green "sponge" filling the water (pond)
like this:

apart from the looks, and use, I also worry about the safety
of any one (child) falling in, and possible pollution further afield.

Thank you for any help in removing this once and for all. jt.

Yes it does look like Hydrilla. Here in the USA it is a problem in many lakes thru out the South and East Coast. In few lakes I fish seen it grow 16 feet high. You can try a grass carp they will eat it. In the Southern parts of the US they introduce a fly that will destroy it.

Good post.

I totally agree, grass Carp are the answer.

They will not breed in the UK (not unless the world heats up na whole lot more anyway!), depending upon pond size, you may want to start out with say 6 and see how it goes.....buy them as large as your pocket will allow, sorry I have no idea what they cost in the UK....

It would appear from the following link that they are cheap in the UK and I also found that they grow to 40 lbs weight eventually....

http://www.uk.gardenweb.com/forums/load/ukponds/msg0508071119624.html

this stuff flourishes due to excess phosphorus and nitrogen from fertilizer runoff. The only way to eliminate it fast is to kill it with a general cell toxicant, along with the fish, insects etc. In some places they make weed harvesters and drag it out and feed it to livestock.

To make it stay away you need to create a critical nutrient, either nitrogen or phosphorus, that you remove from the water by elimination of the drainage fertilizer source. As the plant grows it uses up the CN and growth stalls.

Hello JT.

I think they have answered your question . Chemicals may finally fix the problem.

But - Spray after draining it if you can .

When its looking dead , Fertilize the pond at least a week or so and after the first brown out , then water or fill slightly, then wait for it to grow again - spray it again, to make sure you got all the weed, before refilling the pond. Then do it all over again. Feed & Kill.

Just like Kudzu , is a great problem on the land, this weed is a real problem, indeed. Kudzu has the ability to store everything it needs in its roots, so as to come back again and agian and then again and again. Toradon, by Dow chemical Co is the only fix for Kudzu , as it is a starch inhibitor. Find out what makes that Pond weed tick and then feed it to death.

I would add a liner and insulation and stones too, no matter what size the pond is, be it feet yards or Acres.

If this doesn't work, then Perhaps the Ancient Chinese Methods Will Do ?

The Chinese Water Goat !

http://www.chineseastrology.com/wu/goatyear.html\

Sorry, I just could not resist the temptation to lightning the frustration in your posting - And, I never thought I'd find a good use for my Water Goat .

Really , Best Of Luck, that sounds like a heck of a problem. My company builds landscapes and BIG Water Gardens and Detention ponds, too - & we don't need any of that Stinking weed loose !

Hey -I know a good Priest too , maybe a Exorcism ?

Best Of Luck Ol'Chum,

Joe Woodall, Managing Partner

Georgia Adobe LP Rammed Earth 7 Renewable Energy

2395 Bowman Hwy. NW.

Dewy Rose GA 30634 C.S.A.

706-213-7693

I'll assume that this is a decorative (man-made) pond.

Vote for temperature to 'cook' it.

If your liner will stand up to it: there are gas operated open flame devices for terrestrial weeds.

An industrial steam-cleaner might do better.

Remember to overturn stones & othed hiding places.

Copper Sulfate.

Good herbicide for exotic water plants and roots in sewer systems.It kills water plants and the roots along with Algae.Too strong of a solution will kill fish.I bought it in 50 pound bags to use in my one acre fish pond."IF" I remember right,I used 3 pounds per acre foot of water.I dissolved it in water and sprayed it on.It is very corrosive,so be careful and clean/flush all that it touches.Fish pond supply sources sold it by the pound.It is one of the safer and less restrictive herbicides in the USA.

It will also kill the snails in your pond.

It is also a great wood preservative,but water will leach it out.

Hope this will help.Alfred

How do you safely dispose of this amount of contaminated water after it has killed the weed?

Hello sceptic:

not sure what you mean by 'contaminated'?...........I assume you mean if a substance is used to kill it?

If that is the case, there is no way I can think of to get rid of either the water or the detritus in it. It will not be 'DANGEROUS', AS IN "NOT SAFE" to humans, in the short term. It will or could kill any land growing plant it comes in contact with. And, for sure is not something you should be 'playing with or trying to plant stuff in on 'dry land!

That is why I have said there is no need to deal with the over production of this weed with chemicals.

I worked at a fresh water Fish Farm, and any weed we had after cleaning out our large ponds (about 100 metres²) were put on the bank and left to rot like any other water plant, like for instance bull rushes. It makes really good growing medium. The roots are much like tree roots and take a while to rod down. But, there was so much we could not take it to a dump. It just went to help build up the river and pond banks. After a year or maybe less grass, or whatever other natural plants were buried by it, would come up through and look wonderful.

The original thread started by 'jt', mentions two 'ponds' of 1/2 an acre each, I would say these are lakes really. This area equates to about 2/3 of the 'lakes' we had for fish propagation and growth. When you are dealing with something on that

S-C-A-L-E, it is dangerous, not perhaps to you so much, as to the pond and surrounding area.

If poison is used, and the residue pulled out onto the bank (which it will be), that poison will make its way back into the pond and, if it is poisoned over several years, the poison will build up until nothing will grow in the pond or any part of the garden the pond is in. Even if a completely new pond is made, there is a more than likely chance of the poison seeping into that pond and killing the whole pond life yet again.

This is why I think that recommending and the type of poison mentioned in this thread, on an enclosed water situation, is risky. In the long term, although diluted, it may even reach a stream or aquifer from which the drinking water for the area is taken. .............But, on an acre sized 'pond' this is extremely unlikely.

If however if the 'ponds' are anywhere near a river, or run off to the river, it may well effect someone further on down-stream........................

As a for instance, when we cleaned our ponds out, all the rubbish, although perfectly natural, got washed down-stream to the Water Plant Nursery half a mile away. So we had to warn the plant growers to block the intakes to the pumps which fed water to the plants, for a day or two. Otherwise the filters got blocked and it took a couple of weeks to clear them.................................. Well that 'rubbish could easily be the poison from jt's ponds. And although he may not have meant to..............Well, it is kinda too late by then!

Can I just say in writing this I did not mean to insult anyone on this thread, OK? Just pointing out a few 'facts'.

Sorry for all the words..........Take care.............

Bottle it and sell as herbicide in small quantity

There is a product available in the USA called "Sonar" that is very effective on submerged aquatic weeds but doesn't harm the wildlife. I don't know if you can get it in the UK. It's about $1000US per gallon, so if this shop sold you the stuff in the first place I would try to get them to foot the bill.

If you use an aquatic herbicide in the proper ratios (and you seem to know the volume of the pond) then the fish should be able to survive.

Is the shop allowed to sell this weed? If they tried to sell this in the US they would be shut down pronto for propigating an invasive species.

Good luck. In my experience ponds are bigger money sinks than boats. And that's saying something.

That's rubbish about ponds being more expensive than boats. We got a house with more land on the deal that I got a tractor and she got a pond……… the tractor is definitely cheaper than a boat to run and the pond occupies her so she doesn't spend money on shoes. All in all it seemed like a good deal to me!

Chas

Thank you all - brilliant, I now have new hope.
(The work is still to be done, but now I might just finish the *****)

Special thanks to "grass carp" - I will try these as I'm definitely
partial to feeding something for nothing, and then selling them!

Also special thanks to "copper sulphate" - not tried it yet; will
keep it in reserve, as the last resort.
(get the fish out and then cs it. - if that fails it's napalm!)

I am very symathetic to live and let live; there's room for us all;
but, this "plant" is taking over everything, is a possible danger hazard
(to children) and simply has to be stopped, somehow. (period)

Again, thanks to you all; you're a great team.

jt.

My mother said; "when on the way home from school, if a car pulls up
alongside you, and a stranger says, "get in." Just go."

JT,

just a thought. Float out on the surface of the water a friendly oil, ( we used to use diesel, but we didn't have fish) as the plant needs air and if it's covered in a film of oil I'd think it'd die, eventually. Thinking obout it as I write, a non-miscible oil would be best, as, then you could use a small aerator pump to supply O2 for the fish. Organic oils will eventually break down ( as does diesel, it's organic) under the influence of the sun and other factors.

Just a thought. Hope it helps.

Stu

Just a thought;

When I was a young kid on our farm in southern Illinois we had a pond that was overwhelmed with some type of weed one year. My grand father had us spread virgin straw evenly all over the pond covering the weeds. He then had us cover the straw with regular hay about 6-8" thick. The result was dead weeds in two weeks. We pulled a net across the pond and spread the soggy hay/straw mix onto a field and plowed it under. Our weed did not return. The area of the field with the enriched hay grew very tall corn that year.

Mike

you might be sitting on a gold mine! ????

it sells for $$$'s at the aquarium stores!

http://en.wikipedia.org/wiki/Elodea

Thanks for the thought (wish it was true) but I think
what we have here is a different type of weed. Sorry!

jt.

Then of course, if it's a particularly virulent grower you may just have cracked the fuel-oil supply solution for the world. Drag it out, cold press it and see what comes. The worlds fuel future may be in you grasp. They're working on it allover the place as, as a crop it returns more per acre than most other foliage and it actually does some good for the planet.

That is, if you've got the right weed.

Cheers,

Stu.

I have used Copper Sulphate Crystals to good results, dont overdo it as It may have an adverse reaction with the fish. We used to have that problem with what was known locally as "Duck Weed"

Just put the crystals in a burlap sack and drag behind the boat back and forth across the pond.

Good luck

Ed C

Hello to you jt:, this is aimed it all the short term quick answers on this thread.

Copper Sulphate, STICK IT.............................in the cupboard!

It is a short term gain product. You will not notice it build up in the water, but it will as you add yet more, and eventually you will have a very clear pond indeed.

Clear, because nothing will grow in it! Be patient. 'Nature' is not out there throwing copper sulphate or anything else into situation that are not quite right. Nature waits and eventually finds a balance which we look at and think "I c an do that"! Then rush things and have to restart all over every couple of years.

Anyone around the World, look at your local streams, firstly, those are managed by allowing ducks and other animals in to do 'natures' gardening. You should choose a pond weed and any type of water flora from similar type places to your own pond. Choose from a fast flowing river and, in your comparatively still and small pond that plant has nothing to stop it growing. Have you thought about getting some ducks, they eat lots of weed. They will also eat small fish, as will big fish, so give places for them to hide. Try some of the carp mentioned. And if you do not have any get some 'full' sized goldfish...........also carp. They will eat a little plants but, the answer is a pond liner or, the use of thick grade black plastic sheet to stop any light getting at the weed and allowing it to grow.

You will probably find the weed you have was originally growing in very agitated conditions, such as crocs, alligators and hippo's environments, where there has to be weed which grows fast to survive all the hustle.

Please try ducks, they look good and complete the whole pond picture thing!

And please do not add any chemicals. It just is not necessary.

Spam removed by CR4 Admin

Thank you Kishore for all your info.

I am going to try grass carp and ducks before
doing anything else, thank you.

jt.

Hello jt:

can you let me know the surface area of your pond please?

I like your redirection toward Ducks and Grass Carp. Work with nature right?

I have been thinking that what sounds like a big pond may cost that bit extra to get Lillie's for. But they are essential as surface cover. The way to plant is to put young plants only just above the water and when they are a little out of the water lower them further until you have the full length of stem on the plant under water. Again if you need a lot it may be helpful to get full sized plants directly from a back-water or other large pond or lake? Asking permission and an invitation to show off your pond in the process! I found where the main-stream of the river was diverted there often grew water lilies and, with the water being so deep, compared to your pond, they will easily reach the bottom of your pond. Make sure there is know nasty bugs underneath the leaves and on the stem that could cause other problems. But, if you are having big fish and ducks they will 'polish-off' those for dinner!

Please forgive my rudeness for this advice but, if you have not planted lilies before, plant in the contains, any containers, but allow good sized pots as the tubers do get rather large. Put a good layer of sharp sand mixed with small aggregate on the top of the pot or container. With normal water plant containers you will need to line them with plastic. And lower them into the water slowly so as not to disturb the soil under the layer of shingle.

Good luck and keep us updated once in a while. As you may realise, I still have pond life in my veins still!.

Hi babybear,

Thanks for the info but I already have lilies. (and bull rushes)
(I'd like to get Mary's but that's a bit crude here)

The 2 ponds are about 1/2 acre each, nice but not commercial.

Thanks for the advice.

jt.

We use a blue water coloring is about $6 USD per gallon some folks use as cheap printer ink, won't harm your fish.

The blue color inhibits photosynthesis, you can see where this going

Careful Carp are carnivores and they love goldfish too!

Yes!

Agree with that.

Don't use Carp. They are banned in some countries. They are a blight in our waterways.

Cheers,

Stu.

Hi Stueywright,

I always thought carp were a bit dodgey, - as in dangerous?
But the internet informs me "grass" carp only eat weeds?

How true is this? Any other probs. with carp?

jt.

Thanks bwire,

It's a good idea but the ponds are 200,000 gls and think
the amount of dye needed (to be a success) would be huge.

It's a good idea though as plastic sheets are expensive and,
unless the whole pond is totally covered, (1/2 acre) the weed
grows somewhere in it all the time.

Thanks for the idea though, stain the water to prevent light.

jt.

Hi jt,

You missed something in what was said, take a look here for the coverage area six foot acres for under $80 USD

Thanks bwire,

I will look into it and see if its in the uk.

I'm not sure by what they mean six foot acres?
Six feet deep pond covering 1 acre? (guess)

jt.

Hello jt:

I am also in the UK most of the time. I do not know about 'grass carp', but will google them.

If you have 'Goldfish' or 'shubunkin', a relative of the Goldfish Family. You already have a type of carp. Goldfish are carp. Just in case you are not sure. And as they grow to suit the space available, in that sized pond (two ponds?) they will grow pretty large. You should leave a patch of this 'weed' you do not like for the fry to hide otherwise they will be eaten by mum and dad!

Just a thought, but if you are able to net the pond or ponds with a Seine-net you can then use either a hand shear or a powered one to cut this weed you have problems with. Sorry but I have to say this.......No electric near water! Not for you jt, more fore others who take me literally and just get their hedge shears out which are almost certainly electric. The weed will float and you can then use nets to scoop it off the surface.

Is it two ponds you have, with a waterfall? If that is the case you can always use a fine mesh on the outlet of the top pond and use it to let the fish fry to grow with no danger of being eaten? After moving the larger fish to the lower pool. Or, another way, is to catch as many as you can of the fry and let them grow for a year in a large fish tank, then put them back when they reach 75/100mm.

I am going to look up Grass Carp now.

Hello jt

Here is a bit on Grass Carp. They are not dangurous but can be a pest. However as you will see there is a type of Grass Carp which are sterile and cannot breed. This would be the ones to look for.They do grow large but, any fish will only grow to suit its surroundings. The advantage with Grass Carp, you can eat them!

I have listed suppliers of these in the UK. I would ask about the triploid sterile Carp. Or just get a single fish and limit it to a part of the pond to see if they are going to eat the weed you want rid of.?

DO NOT EVER RELEASE ANY INTO LOCAL RIVERS! They are safe and, as I say will grow to suit their envioroment and I doubt they will get anywhere near the 4' (1200mm max). They will in large rivers where there is lots of room, but your goldfish will also grow to a larger size if released into a river.

Hope this helps. You can order fish by post by the way! But, unless they are sterile, the sex of a fish is guess work really so, if you order three fish you may get three males, three females or a mix. In which case they could breed. But, not if you get Triploid or sterile Grass Carp.

• Grass Carp For Salewww.rippleswaterlife.co.uk Natural aquatic weed control delivered to your door 01952 200199

  Search Results

  Grass Carp - Wikipedia, the free encyclopedia The Grass Carp (Ctenopharyngodon idella) is a herbivorous, freshwater fish. It is cultivated in China for food but was introduced in Europe and the United ...
  en.wikipedia.org/wiki/Grass_carp - 31k - Cached - Similar pages Grass Carp help, advice and information on fishing for grass carp.
  www.maggotdrowning.com/fish/grass_carp.htm - 10k - Cached - Similar pages Pond Management Guide - Chapter 4 Grass carp occasionally provide partial control of duckweed, ... Recommended grass carp stocking rates are generally 10-15 fish per acre in small ponds and ...
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  Grass Carp

  From Wikipedia, the free encyclopedia (Redirected from Grass carp) Jump to: navigation, search

  Grass Carp
  Juvenile Grass Carp
  Scientific classification
  Kingdom: Animalia Phylum: Chordata Class: Actinopterygii Order: Cypriniformes Family: Cyprinidae Subfamily: Cyprininae Genus: Ctenopharyngodon Species: C. idella
  Binomial name
  Ctenopharyngodon idella Valenciennes, 1844

  The Grass Carp (Ctenopharyngodon idella) is a herbivorous, freshwater fish. It is cultivated in China for food but was introduced in Europe and the United States for aquatic weed control. It is a species of carp native to Siberia and northern China.^[1] The alternative name White Amur derives from the Amur river, where the species is believed to originate. This is not to be confused with the White Amur Bream (Parabramis pekinensis) which is not a particularly close relative as Cyprinidae go.

  Contents [hide]

• 1 Appearance and anatomy
• 2 Ecology
• 3 Relationship to humans
• 4 References

[edit] Appearance and anatomy

Grass Carp White amur have an elongate, chubby body form that is torpedo shaped. The terminal mouth is slightly oblique with non-fleshy, firm lips, and no barbels.^[1] The complete lateral line contains 40 to 42 scales. Broad, ridged pharyngeal teeth are arranged in a 2, 4-4, 2 formula. The dorsal fin has 8 to 10 soft rays, and the anal fin is set closer to the tail than most cyprinids. Body color is dark olive, shading to brownish-yellow on the sides with a white belly and large slightly outlined scales. The grass carp grows very rapidly, and young fish stocked in the spring at 20 cm (8 inches) will reach over 45 cm (18 inches) by fall, and adults often attain nearly 1.2 m (4 feet) in length and over 18 kg (70-90 pounds) in weight. They grow 10 pounds a year at least. They eat up to 3 times their own body weight daily. They thrive in small lakes and backwaters that provide an abundant supply of fresh water vegetation.

[edit] Ecology

This species occurs in lakes, ponds, pools and backwaters of large rivers, preferring large, slow-flowing or standing water bodies with vegetation.^[1] In the wild, grass carp spawn on riverbeds in fast-moving rivers.^[1] Adults of the species feed exclusively on aquatic plants. They feed on higher aquatic plants and submerged grasses, but may also take detritus, insects, and other invertebrates.^[1]

[edit] Relationship to humans

The species was deliberately introduced into the United States in 1963 for aquatic weed control. It was introduced into New Zealand along with stocks of goldfish but the distribution is carefully controlled to prevent it from becoming a more widespread pest. The Grass Carp is considered an invasive species to North America. It is illegal to transport or own Grass Carp in all but twelve U.S. states because of the threat Grass Carp have on native plant species.^[2] The species was introduced in the Netherlands in 1977 for aquatic weed control against overabundant weed growth. The release of grasscarp into national water is controlled and regulated by the Dutch Ministry of Agriculture, Nature and Foodquality. Because grasscarp only reproduce in water of 25C°, which is much higher than the water temperature reaches during the mating season in the Netherlands. Because of this, it's mandatory to maintain grasscarp populations by artificial means, which is done by the Dutch Ministry of Agriculture, Nature and Foodquality. Because of its special function in controlling weed growth, grasscarps should always be returned into the water alive and unharmed. When used for weed control, often the fish introduced to the pond or stream are sterile, triploid fish. The process for producing triploid fish involves shocking eggs with rapid change in temperature. The young are then tested for triploidy before being sold. Bait often consists of vegetables or fruits that are native to the area.^[3] These fish are also a food fish, and may be steamed, pan fried, broiled, or baked.^[1] Grass Carp can be caught using a Bow and Arrow.

[edit] References

Hello jt:

Just a couple of points.................

Are both ponds in use or is one empty?

Did you see the Stock recommended for your size pond is only 8?

Hope everything comes out alright in the end. It can often take a couple of years for ponds that size to naturalise. There is a lot of water, but, there is also an awful lot of evaporation. Thats where the Bull Rushes and Lilies and, any plant that gives shade will help.

Can I just say, when I mentioned 'plastic', I was not referring to a pool liner. They are expensive! I was thinking that if you had an empty pond you could use ordinary black sheet say 12' wide to stop any light getting to the remnants of weed which may be in the mud. You can also do this in any pond which is 'in use' as you clear the weed lay the thin plastic down, until the weed grows less.

You can also send a sample to a TV gardening program, who may even be interested in videoing your pond and its progress? Alternatively you can ask advice from HDR, (Henry Doubleday Research). Here is the email. enquiry@gardenorganic.org.uk

I can imagine the size now as a friend had a one acre pond, well a lake at your and that size really. Whatever you do will be hard work, but, the one advantage is it is oxygenating weed and so will help prevent any algae taking over the pond.

I think any good sized fish, (and with that much space they will grow pretty large) the weed problem will gradually be over come, as any ornamental fish, goldfish (actually carp), etc and of course the grass carp with disturb the roots if they are in soil, and they will float to the top and then is the time to skim them out before any can be 'reseeded'.

Good luck anyway.......

take care

Thank you babybear for such a comprehensive answer!

I had done a bit of googling myself, and it made me indecisive;
but will try a few grass carp, before doing anything else.

Many thanks for all your time and effort; and to everyone else;
we should have it beaten now. Will report in about 2 years time.

jt.

Hello jt:

can I just suggest, that, if you have both ponds in use and both have a problem with this weed. Try the grass carp in just one pond, or if at all possible, divide part of the pond off and put the grass carp in there, and wait to see if they make a difference?

Good luck, and hopefully you will not have to wait two years if the grass carp are hungry!

That's exactly the one, babybear.

Thank you for your continuing interest.
This is pretty comprehensive now, and I intend
to try grass carp first, herbicides later if they fail.

Many thanks for your help.

jt.

Hello jt

Grass Carp.........You will need half a dozen at most. And as I was reading stuff today, it mentioned Grass Carp as a good way to try and cut the weed down. I read the are two basic types. As with the Grass Carp, the plants are 'Triploid' female, or something like mouicea. I know that is not write but I did not keep any shortcuts for Kew and other sites I went to. The second is the one you have. The first female type does not spread and does not replant either. It is your bad luck!

It appears that the plant has been positively identified as Hydrilla. If this is indeed the case, one technique I can tell you is not worth trying is adding blue dye into the water. Hydrilla can survive in very murky water with very little sunlight. I have been conducting research on it as a possible plant for use in free water surface constructed wetlands as its hardiness, strong oxygenating capabilities and phenomenal growth rate make it very effective at removing pollutants.

One experience I can share with you is that this is one really tough bastard that can really take a beating. It would be interesting to see how it stacks up against a shoal of voracious grass carp. Keep us posted will you?

Hello DVader1000:

If as he suspects, this is the horrible Hydrilla It is extremely good ay what it does. Soak up foul water and grow. In a normal sized pond there just might be a chance, but with each pond at 1.2 an acre, I honestly do not think there is any way to get rid of it. A normal say, 12 X 6 feet pond you can easily reach all the pond and get all or most of the weed out in an hour or so. Even in deep lakes it grows. Either too much or not hardly any mud on the bottom and it likes it both ways. I think the only way is to leave one pond/lake empty. And depending on the pond base or bottom, try to keep it dry or even try something drastic like brushing tar on the dry bottom or, the concrete and see if any of this weed starts to grow through next spring.

Assuming as he has said, he does not want or afford to line the ponds with proper Butyl liner, another course is to spray or brush water hardening cement throughout the ponds. Spray the sides lightly with waters and it with go hard even under water. Then next spring, just put a few inches of water in and see what happens.

Even in a dried out pond it lays dormant ready to start to grow. The tar and cement maybe even in layers to treat an empty pond, will be the best way to go.

If the weed grows unchecked, it could easily leave no water for the fish to move around. What ever, it has to be depressing. After all the work he must have put into building those ponds.

Bye for now..........

Hello baby bear,

You are quite knowledgeable of things aquatic and my suggestion of blue dye is better for algae and other scum. What would you think of using salt to deter or curb this weed?

Hello bwire

You are quite knowledgeable of things aquatic................ Its coz I'm a hexburt in it?!

I am really sorry this is so long. but, I hope you find something which explains my reasoning. And I will copy and paste the details I read the other night if they are not in one of my last posts to thingamebob!

To get me posh voice now........That was a jolly good show old boy!

About the note you sent on blue dye; and salt.The blue dye thing I had not heard of before. But, I can imagine, in a relatively small water area, :

1) I would not be certain it was not toxic.

2) It would be so easy to add too much and either have the pond go too blue to see anything in it; kind of defeating the object!

Or, you could end up with green plants and anything else, perhaps including the animal life as well, turning blue also?

I have been reading about the weed (and I am sorry but I have forgotten his name) he says he has. It does sound like it. If you follow some of the links I sent him you will see the yearly life of the plant explained. Including the variations in colour from brown to green and a few colours in between. This all goes to help prove or otherwise if it is the horrible weed. And that same piece which explains the colours, leaf shape, and habitat, which is also on banks as well as backwaters, says it has tiny male and female flowers. These are only 1 or 2 mm across so may not even be noticed by a lot of people. To breed it sinks back down into the water and breeds through the water, with the different male and female sexual organs (again I cannot recall them, sorry) release their 'stuff' and their life continues. I will look at the piece I sent him and if I can find what I was reading for about 8 hours the other night I will send them by PM to you. Either this same piece or another goes on to say, and this is with ref' to your salt idea..............this plant can live in extremely saline conditions.

So it would seem that line to fight it is out.

Salt actually 'grows as a crystal on any place which is almost dry.

So as long as you were able to flush it out or just take time to keep washing it from the sides of the pond, which if it was full would be underwater., it would still not work because Grass Carp can handle the saline water. Normal fresh water fish like goldfish etc, in an enclosed environment can't take much salt. So I do not think that will work even in a dry pond.

The Grass Cap however, will love it while its smaller friend's pop up and float one by one

I have seen ponds which are sterile because people have followed the 'fashion' and bought the latest 'do it all' and 'magic pond clearer'. If you enjoy water-gardening, put the pond in (all be it on a much smaller scale than our friend)fill it with water and waiting the two years or so for it to naturalise, you can then enjoy your 50P goldfish, or your £20,000.00 Koi Carp.

A big mistake almost everyone makes is to put the water and plants in at about the same time. You should leave it full with water for a year before you put the plants in, then at least six months again before you put the animal life you bought to go in there. By that time you will probably see frogs and toads and other life which has found your water and has started to naturalise it. Removing the salts like chlorine etc from the water and leaving the water which may be cloudy, as things start to come to life ready for the fish and other stuff.

Trouble is adding all kinds of chemicals, you cannot see them, and they seem to be taking forever to 'work', so you add more and more which buggers up the little mini food chain you have created and not just the fish but, the snail, plants, and insects, and plankton gradually fade away, then if you get a bad winter the fish have nothing to nibble at in their larder, they die one by one and next spring they are all floating on the top.

It takes very little in the way of chemicals and other pollution to knock out a wonderful stretch of river. I little soap, perhaps urine, whatever. It will take 10 or 20 years for that 'dead' part of the river to restock all the essential nutrients and make a habitat for the fish that used to live there.

This situation usually happens in back-water, Lakes and water that has been badly managed by the people who should know better. Instead of a fast flowing water-way, there is lake conditions now in this part of the river. Anything which made it like this cannot be washed away because the water is virtually still. And, of course the outside insects and birds no longer.........can no longer live in those conditions. The only way to put that right, is to get people hands onto, make the narrow dead 'river' wider and drag all the usually dead stuff found in a place like that out, and widen the river and go back as far as you have to, maybe miles, and get another water-way to flow through there and to bring with it new life.

We have several relatively narrow rivers where the average width along it length in 20ft, but you will find the mud at the sides turns to graven and quite large stones in the centre. That is done by about three things, all going to make it a healthy river. The first is ducks and other water foul. Second the fish and shrimps and other animals making little beds to mate in. They and humans. Used mainly to control the banks to stop those wonderful bulrushes from taking over. But in the smaller areas in the big river it is the healthy life moving the river bed about to do what comes naturally. Or fish and birds trying to escape other chasers which also go to make the bed free from large amounts of weed.

Not because the fish eat it. But, because there is so much going on the plants which have not adapted cannot find room to start growing and so the river, even tiny ones, are healthy.

Thank you, as I recall the plant thrives on nutrition from farm run-off. Could these ingredients be increased beyond the plants tolerance threshold and could such method prove toxic? Of course the gold fish would need a temporary home.

Hello bwire,

yes not good for the pond or anything in it but, yes, the run-off would be toxic to this plant as far as I can see. Plants like a little nitrogen, but not drowning in it. That is why anywhere round cattle sheds are just mud.

I think he should make a much more modest pond........very much more modest pond! put all from the problem ponds in there, but no weed! The difficult part would be to clean the ponds out afterwards, enough to be able to support animal and insects.

I have read that the plant can survive as a rhizome for several years in dry periods. So whether the rhizome could survive after being buried in shi-?

Myself,...............I would start all over again. build a natural pond but on a slight clean plateau, and have some edge to the pond to stop the run-off thing.

It would mean no more work than trying to clean the weed from the ponds. But the pond must be on a plateau. Perhaps a large gravel base with a hole dug in the centre? Must be raised.

Some good thinking there wire!

I think he should make a much more modest pond........very much more modest pond! put all from the problem ponds in there, but no weed! The difficult part would be to clean the ponds out afterwards, enough to be able to support animal and insects.

Thanks and since my thinker is working today I'll add a little more thinking

I think I think you're onto something an I'd like to comment on it. He (jt) could dig out the ponds instead and build up the bottom again maybe incorporate some fingers or lands and create channels about twelve feet wide. This could help manage a pond system ya'think.

Hello wire,

yes I do think! The spits of land could become a feature with bridges, or even simple stone or log steps. And, yes it would still be as big but the spits or bridges could incorporate Zinc mesh which would allow water to move throughout. But the whole thing is more manageable. Bugger getting a boat out each to I have to do something!

If you feed the fish from the bridge/s you can have more control and put in just enough so it is all eaten. Fish find a lot of insect life frog spawn and baby sons and daughters (unfortunately) to help them get a varied diet. They rarely need feeding. And a lot of problems can be tracked down to over feeding. It will also cloud the water. But you should add just enough for the fish you see to finish, before it reaches the bottom.

I have checked with the posts to jt. And there is a number of links one some of his longer and plant specific posts I sent. If you have not done so..........WHY! There is also some stuff written in the post where you do not have to link.

Nice one bwire!

Hello DVader1000:

Just remembered the name of the cement. It is Portland Cement. It is used by itself, no aggregate and brushed on, or skimmed. I am thinking he can do it in the empty pond, then if it works, do the same to the other one.

One thing though. He has to take care not to leave any bits of this weed anywhere near any water, pond or not, as the research I have looked into says it grows in and out of water, as long as the is moister. If it starts getting growing on land, then the flowers form it could easily blow into the water and the whole thing starts again.

Take care..........

Hello jt,

you say it is the one..............But, they look so much alike trying to compare them is difficult unless you have a known 'good' sample of one of the half a dozen or so varieties sold at many garden and fish places.

With a problem like yours I would definitely get one of the gardening programs from say the BBC, interested. They might be able to offer more help. And even do it for you under a sub heading of 'the weed man', over several weeks or months?

I would also dry a young and more mature stem and send them to Kew for confirmation as to the exact strain...........I do not know for sure but, they may be able to say you can put an insect which eats or damages the plant in with your other pond creatures?

Good luck..........

Have you tried changing the ph say to an alkaline state?

I have followed this with considerable interest and particularly appreciated baby bear's expertise.

The weed looks the same as one we used in Mt Isa (a mining town in far west Queensland, Australia).

We had a situation where the River was either flooded or not flowing at all, consequently, when it came into the dam for our main water supply, the water was very muddy.

To enable water to be used, after the mud from the flood had settled, clean water was pumped into a separate dam and this was used to supply the mine, smelter and town for the few weeks a year that the turbidity was unacceptable.

A scare emerged when it was thought giardia might get into our water, so plans were made to build a sand filter.

Someone built a channel to direct the flow from the pumps to the far end of the lagoon so any water extracted had to traverse the entire length of the lagoon.

To all except one person's surprise, the weed ( I suspect it was Hydrilla) cleaned the water so well that turbidity fell to a little below what we could have achieved with a filter! (The one person not surprised was MIM's Ecologist who had suggested it in the first place).

Your carp may well control the weed. I strongly suspect you have little chance of eliminating it. The weed we had had strong rhizomes deep into the mud. These could withstand prolonged drying out and just about everything else. In our dry tropical conditions the weed grew very vigorously.

I remember that our ecologist took some care to keep a healthy fish population in the clear water lagoon to prevent the weed getting out of control.

The fish also controlled the cane toad population (a big pest in the area as it wasn't native) by cleaning up the eggs and tadpoles. The adults were toxic.

A secondary potential problem was heavy metal contamination form natural ore bodies in the catchment. The weed seemed to reduce this also.

Depending on what you are actually using your ponds for, with proper control this weed may even be an asset. As you have found, it can easily get out of control.

A healthy overall ecological balance, with a good collection of weed eating fish would seem the best method of control.

While grass carp are probably your best bet, I would suggest a balance of different fish to reduce the chance of unintended consequences.

My knowledge of the subject is too skimpy to be able to suggest exactly what balance you will need.

You seem to be getting plenty of sound advice from far more knowledgeable people than me.

Good luck

Hello sceptic:

You seem to know something about the weed and are quite knowledgeable.

As you may see I have posted a post to bwire and have said I think the only way forward is to fill and forget these ponds. Start over again with everything taken from the other ponds but no weed

My thought as I was typing was to build it on a plateau. maybe a few lorry loads of gravel and sand levelled out but still with raised edges with the pond in the centre.

Of course the best way would be to build in an area which does not has run-off from the farm.

You said about balance in stocking. He may well have that apart from the weed going crazy! Use orf, golden and silver Orf for top dwellers goldfish and shebunkin for midway down. And tench or catfish for the bottom. Actually, I wonder if he has any large tench or catfish? I would imagine they would stop any rhizome activity with the constant moving back and forth through the mud.

I have seen any weed completely take over a backwater until it pushes out of the water. Some may die which does not get wetted enough but, it is just because it is in the wrong place. In that situation, if the water is not too deep just walk through and push your way through the weed whatever it is. It will float and be washed further down the water-way. Once it has gone water will flow faster and any build-up of mud will be washed away soon as well.

A river however small or large can soon get blocked by a fallen tree or bushes. All our wonderful water, river and lake are 'Managed'. You can tell badly managed ones as the banks are growing closer together in parts, rather than being more or less the same width throughout its length.

Take care and, thank for the nice stuff you said about me.

Exactly. Hydrilla is useful if you're creating a FWS wetland to purify water, BUT, care must be taken to ensure it does not escape its confines. I'm a little sceptical about letting the hydrilla drown in nitrates though, because either it will cause the hydrilla to grow wildly out of control if it's insufficient (as if it isn't already), or, if it succeeds in killing the hydrilla, then it will also result in severe eutrophication that will kill everything in the lakes and stink up the area for some distance around.

Personally, what I would suggest is to use a dredge or something similar to pull out as much of the weed as possible, and then introduce the grass carp to eat up the remainder. Right now, the reason why the plant overran the lakes even after being dredged out is because there's nothing in it that will feed on the plants. Remove most of it, and then introducing something that will prey on it, and you may stand a good chance of, if not eradicating it altogether, then at least of keeping it under control.

As for the dredged out plants, I would suggest composting it. After all the grief it caused the OP, he might as well make good use of it.

Hello DVader1000:

you make a good point on the idea of dredging! It may be the only way to stand a chance with the Grass Carp and perhaps also a couple of ducks, just to see if they actually eat any weed? There must be a ton or more of the weed at the moment, and any number of Grass Carp is fighting an uphill battle.

You sound like a thinker, and this situation needs thinkers!!

As I said in another post I think jt should try and get the largest carp he can. Even then I doubt 6 Carp (which is the recommended stocking rate) will be able to control this weed. Nice to think it will, but, I would just start again, building my new pond on a plateau to prevent any run off. Which in the long run will over contaminate the pond whatever its size?

Take care............

DVader's suggestion of mechanically reducing the weed before introducing the carp is a good one.

I think starting again with new ponds is probably unnecessary. A healthy, balanced pond will handle and clean up quite a bit of pollution.

I see in another post, babybear has made some good suggestions about types of fish to stock to handle the various levels and balance the pond.

Do any of you know of bottom dwellers who eat weed - specifically rhizomes?

From memory the rhizomes on hydrilla are very persistent.

It may be necessary to find some bugs to help eat this plant. Again at Mt Isa, Lake Moondarra, the main water supply dam, was choked with salvinia. Research indicated a predatory bug which was trialled with limited success. A large thunderstorm fixed considerable nitrogen (as tropical thunderstorms are prone to do) and dumped it into the lake.

Within a month the salvinia was restricted to a few minor pockets. It was then realized that the bug needed nitrogen to be able to do it's job. That was March 1981. Since then this bug has been used to control salvinia infestations around the world and when used ammonium nitrate is scattered on the salvinia blanket first. The one seeding is enough as the destroyed salvinia then adds enough nitrogen to keep the process going.

The point is that finding and establishing the right balance to achieve an acceptable environmental balance can take a little experimentation, but once achieved it tends to be self regulating and quite stable.

Touchy, fragile environments are usually ones where an artificial balance has been achieved and this is seldom desirable in the long run.

I think the best solution is probably to dredge the weed to reduce it's mass; compost the weed removed; stock with grass carp and probably some catfish, possibly also bream if they will handle your conditions. You should then have a fish meal occasionally to prevent your pond overstocking itself and you may even wind up glad you have your *** weed!

Best of luck

Hello sceptic:

you make some fair remarks and add to the list of info, thanks.

With regard to resiting the pond or, removing the stuff other than the weed from the two old ponds..........It looks like run-off from the Farm is a possible cause which gives this plant sustenance. So as he said was going to do work on the ponds, and I think also mentioned about filling one in, I thought he could put the same time and effort, into simply getting a few loads of gravel, levelling it out leaving a slight raised mound, then dig a new pond transferring all the stuff from the new ponds, including the water if it is clear. It should work better than using fresh tap water as it will be at least partially naturalised? That way the pond will have no weed and will be raised very slightly to prevent any run-off from reaching the water. It would take not more effort than filling one or both ponds in, and is likely to be successful, as long as every part of the weed is removed on transferral?. Just a suggestion, on what must seem like hell after all the work to build the Lakes, really, they are too big for "ponds".

There is two types of bug able to live on and even damage the weed which is mentioned in one of my two main detailed posts on this plant. And may also have a link in the same post. Not sure about that.

You have obviously put a lot of work and thought into this subject!

Thanks for your post

Hello wire,

Why has this post been voted 'off topic', because it referred to a link that is very much on topic?????

With regard to that site, I know I visited it in the last two days, and most if not all details are in my post #50. I may have thought that the title 'The Perfect Water Weed' may of put the original thread writer off a little, as I certainly was not for him. I may have copies some and compiled it together with a UK site where I got the alternative name (at least in the UK) of Esthwaite Waterweed.

This is the site I pasted post # 50 from.........http://en.wikipedia.org/wiki/Hydrilla

I think the site you linked to which I had read, I thought was inappropriately name for this thread.

A lot of the details can be cross referenced (is that a word?) The weed certainly seems to have found its huge niche around the Equator?

Very interesting plant.........

Take care.........

Hi Baby bear,

But it is pertinent the name I mean; it is a superbly developed aquatic plant.

Did you notice the comment regarding it's ability to survive the digestive tract of water fowl and that it may be distributed by that means.

From the notes I've seen it seems well adapted to the higher ph values though no mention is found of a resilience to acidic conditions unless I'm mistaken.

I suppose jt may be well to alter his planned use of the ponds.

Can you think of a purpose for this situation?

Hello wire,

do you mean the name with Royle (Hydrocharitaceae), at the end? Other than that, the first main part of the name sums it up! As water plants go it is up the with the ANTS, which are on just about every continent. I suppose the land plant to equate it with is the grasses, which again live on just about every continent.

Yes I did see that bit about was it water foul regurgitating it or something?

I have just been reading about the insectivorous approach. It seems it is most effective in Pakistan where the insect come from as the plant spends part of the year above water. When it is below water the insects can not get to it. I assumed when I mentioned insects a few posts ago if they lives on water plants they would be able to live underwater at least some of the time.

But back to the king of plants. It is for sure, though don't go telling jt that!

Take care

Unfortunately, as I mentioned earlier, like kudzu, Hydrilla is damned near indestructible. It can survive a pH as low as 5.0 to as high as 9.0. As far as I know, it only has a few natural enemies such as grass carp and a few insects. From my personal observation, tilapia may eat it when hungry, but I don't know how effective at eradicating it they will be. A combined attack plan would be the best option to control it. As for destroying the rhizomes, aquatic mammals such as water voles or beavers may eat it, but they may also be more trouble than they are worth.

Hello DVader1000:just to say, yes water voles are a damb nuisance, but beaver can re-direct a river. It is difficult but the choice is water vole if I had to choose.

Back to the thread. I think the Grass Carp was your idea? That and a family of ducks, who would probably eat mote of the weed than the carp, but a combined attack is needed for sure. Too risky and may be unlawful to put any foreign insects in to help. But there must be native insect who lived on it where it was first discovered the HYDRILLA H. verticillata (Esthwaite Waterweed) in Estwaite lake? I will check on it. If it is native to the UK jt may be able to use them?

I think the Chinese Water Goat should be given a chance

Take care

Great idea. I did mention earlier that introducing insects may not be a good idea because unlike grass carp, they can escape into the wild and cause ecological problems. Native insects on the other hand shouldn't be a problem. So let's see; plan of action:

1. Dredge out as much hydrilla as possible.
2. Introduce grass carp to eat greatly thinned out plants.
3. Introduce ducks to eat uprooted plants and possibly uprooted rhizomes. Use dredged up plants to feed ducks to acclimatize them to the taste of hydrilla if necessary.
4. Introduce native insect enemies of hydrilla to weaken plants further.
5. Repeat until hydrilla's food reserves exhausted, finally killing the rhizomes.

Yup, sounds doable, and possibly achievable in months, not 2 years. Best time to start? Probably early spring, just as the plant starts growing again after resting for the winter.

Hello DVader1000:

looks like you have it all mapped out! A friend has an 1 acre lake, so I have some idea of the problems. And one is possibly having to use some sort of boat or raft? I think wires idea of little spats of land to make it easier to manage should be checked out.

It is actually a good job the pool is not the usual 12' x 6', because if left to grow while on holiday for instance, this weed is capable of sucking all the water from the pond up into itself. Not much consolation for jt.........

We could adjust the depth of the ponds in the Fish Farm by sluice gates erected as the ponds or lakes were being built. So we used to bring the water down from around ten feet, to 3 to 40 feet. That way we could don our very fashionable waders and get to the centre of the lakes. But that needs a completely new start and somewhere to run the water off, ideally a local brook or river, which should have the pipe-line in before any water in allowed in. Quite a bit more work but, if I had a back hoe or something it would cause no pain. It just makes the whole management thing really, as you say, "doable".

Take care and I am sure others who have not written in are finding this thread gripping! There must be many more who look rather than join, do you not think?

Take care...........

Great answers, and great ideas there. Thanks for the kind words, but if I appear to have come up with what may seem like a workable plan of action, it's only due to the combined ideas of everyone here who took part in this discussion. As an environmental engineer, it's my duty to contribute towards remediating an environmental problem, and I'm sure poor ol' JT will agree that the hydrilla has turned his lakes into an ecological disaster zone.

Thanks everyone, for your ideas.

Hello DVader,

I also thank you for your kind words. Yes you are right, it was really a group effort of about 5 or 6 kind and helpful and knowledgeable people. I do not include myself in that group. It is for others to say whether I helped or not. I just really like anything to do with any waters really. But learned a lot and became really interested in the plant side of water-gardening. I find it amazing that the Latin names can fully describe the colour, size, type, location, etc, ALL in one or two words. To do it as well in English would take several lines!

As you say "poor ol' jt"! After already doing a huge amount of work to built two half acre ponds and stock them. To find a problem like this is thoroughly disheartening.

It just needs time, and or, the whole Family getting their 'Wellies' on and getting through it in a fraction of the time. Of course the machinery will save time. As long as jt takes time, and perhaps this is where the Family enter, to check there is no fish or anything he wants to keep, still in the weed.

Thanks and bye for now..........

I can really say, thank you all. Your replies and concern
(effort) is appreciated and most gratefully received.

At least there is now an armory of further means to
control this weed. While cementing, plastic liners, etc
are initially considered too expensive it may become
necessary to resort to these extreme measures.
Which is a pity, for natural ponds with a clay base.

Meanwhile I have ordered some grass carp, and will if
need be, consider filling in the pond for a year or two,
and then re-digging it out again; if, I cannot find a use
for this weed; a path I rather would not travel.

Maybe for me to start a carp fattening farm or such like,
then perhaps even I could eventually end up "thankful" of the
water garden who actually "sold" me this weed, who knows.

Again, many grateful thanks to you all for helping me find a
way forward with this "alien" "Bas***d plant, which has taken
over not only the ponds but also many weeks of my time, and
quite a bit of money truthfully attempting to clear it.
With your help we will conquer all, one way or another.

My best wishes to you all,

jt.

Engineer - To arrange, contrive, bring about.

Hello jt,

it is pretty sad that you put so much work into the two ponds and you may have to fill at least one in. A large water area where you cannot reach the centre is hard work to do anything with. Just checking it out could take an hour or more.

Good luck, and I hope we get an up-date in the future.

Hello jt,

May it be you have stumbled opon a cottage industry or possibly a biomass source.

What may be the result if used as mulch after drying or if processed in a pellet producing machine either as fuel to burn or a soil conditioner (humus).

Hello bwire:

I think that idea could be helpful. I have read the plant cannot be fed to cattle but, mixing it with say corn husks which can and hey presto, it is gone.

Good sugestion.

This weed is not useless! I live on a small pond, that has it's share of weeds. In years past, I had a good size, (organic), garden. I often harvested and composted the weeds.

One year I had the bright idea to harvest and burn the weeds, to help heat my house in the winter. I modified a log-splitter, to form the weeds into a "log". Then they were layed out and dried in the sun. I actually cut my wood usage by about 20% for that winter. I gave it up though, it turned out to be a little too labor intensive, and messy, to repeat another year.

Hello Bricktop:

I know it is not useless. And I have said if he can see through the weed he will see nice clean water!

I have suggested getting the gardening programs on the TV interested, and they may well clear his pond for him. But he has not mentioned that in any reply.

Another option is the chance of a nearby animal park or zoo harvesting this stuff to help get rid of it. An acre of pond is a LAKE, and that much weed is almost impossible for one bloke to combat?

Anyway, take care..............

Living on a pond myself, I got interested in this thread. I found a wealth of information through these links:

http://aquaplant.tamu.edu/contents/links.htm

Hello Bricktop:

thanks for the link. I would love to be around water. But finances do not allow it. All those kinds of great places are too expensive for me.

I will look at that link later.

In reply (to the latest):

My pictures (above) are virtually identical to the named plant;
and (to layman me) I have no doubts they are the same one.

I have not contacted the media (only CR4) because I think their
input may not be any better than the very informed help from your
good selves and, do not wish to create a saga of this problem!

I understand (so I am told) it will take about 2 years for the carp
to make any impression and, if you can bear with me folks, I look
forward to hopefully reporting the (carp) success here later.

Many thanks for all your help. (it's great)

jt.

Hello jt,

Thanks for the note. I was just thinking they could perhaps solve this as they would be 'there', and may well clean the ponds out for you. Anyway I appreciate what you have said. With regard to the carp, try to buy as large as you can afford, or find. A 6" fish will be lost in your ponds. If you are able to find any which are a foot or more they will grow and eat that much more. They say to have about 6 Grass Carp in one of your ponds (trying to recall the details but my mind is playing tricks).

Even if they say these fish consume there own weight in weed per day, the weed will grow much more than the fish's weight each day. But I would also try ducks, or two to start to see if they will eat this weed. Try and get sterile Triploid fish, they can't increase in number and there is no danger in putting them in a river. I would get maybe a dozen and have fresh fish on the menu for yourself. That is if you can catch them.

Good luck my friend

Thanks for your advice and wishes babybear; will do.

My very best regards.

jt.

Hi babybear, bwire, DVader and jt.

This has been a very interesting thread. It is particularly interesting to follow how the expertise of a couple of people, coming at the problem from different backgrounds, readily produces a workable composite solution.

babybear, re new pond. As you explained, this need not be significant extra work. It doesn't have to be elevated, all it needs is diversion banks to direct drainage around it. The result would be similar to the "turkey's nest" dam used on the cattle stations in the outback. There they have extremely flat ground (200' fall on the Darling River in about 2000 miles). To prevent the water supply for their cattle being contaminated by flood water, the walls around the dam are raised about 6' above the surroundings, and water is pumped in from a bore. This water in turn is then fed to the watering troughs.

One caution, do not use any of the water from the existing dams to fill your new one. small bits of hydrilla in the water can restart the whole problem off again.

bwire. That link #80) was terrific!

One point I noticed is that hydrilla can use carbonate/bicarbonate as a CO2 source. If the pond is sealed with cement, the CaO derivatives readily change to carbonate. Hydrilla can use this carbonate when other plants can't, tipping the balnce further in favor of the hydrilla.

It is also likely that raising the pH will also only benefit hydrilla relative to everything else.

This is one tough **** weed.

DVader. I neglected to mention that I appreciated your comments about using hydrilla in wet lands for cleaning up low quality and contaminated water. It does this very well and this is an excellent use for it. Everything hinges on getting an acceptable ecological balance that is also self regulating and stable with only minimal inputs. I'm sure jt has better things to do than spend his time maintaining these lakes.

jt. What do you do with these lakes? A lake for water sports would have a very different acceptable balance to one used for fish raising. If they are sumps for farm drainage another set of factors come into play.

This discussion has been very interesting so far and I have certainly derived a lot of pleasure from following it.

Best wishes

Hello sceptic: I like the way you sort of 'creep up on us, thinking you may be going to say something completely different..........Well, I am looking for my trunks! Oh, I can't swim, blow!.........And, yes it is longer that sceptic's, well I have no one to talk to apart from on here, (and don't I make up for it!)

I thought DVader, and bwire were about equal. With DVader giving a really good description of the plant before bwire sunk the black with post 80. You helped in no small part either sceptic!

I was just throwing ideas at a problem that seemed insurmountable, and still may be. But The Grass Carp.......DVader? And ducks, ahem, me, I think they may prove a winner when the bulk of the weed is removed. So but I do not recall to whom that point goes.

Just one point. If he built it on clay, which I believe he said. Chances are it may have been streaked with chalk? Which would have the same effect as the cement would?

I thought I remembered reading about the carbon metabolism, but also had in mind what I was going to bwire and copy, and that was the bit about cement, and if not suitable to the plant, then hot tar. Though this would have been a desperate choice.

A point has to go to ozzb for the first naming of the plant?

My personal choice would be to build a slightly raised pond, may be a half to a quarter the size, with something to prevent and run-off reaching it, even in the rain, and we do get a bit of that sometimes........ Or maybe have the same sized water feature, but made up of two or three ponds. Each pond having a type of simple sluice gate to help stop contamination of its neighbours. I also think it was bwire who mention slivers of land or pontoons running in at diverse angles, sorry can't recall it in detail, but it would make it easier to manage without getting the boat out!

I really hope jt can crack this. Well, I know he can, it depend on time and cost really, and, unfortunately we cannot help him there.

Thanks to all for a really good 'meeting of minds'.

Tonight I saw this program http://www.abc.net.au/tv/newinventors/txt/s2494979.htm

If you need to go the herbicide route, which I am sure will be a last resort, this may help.

I'm fairly sure that the route suggested earlier will solve your problem, but this link looks interesting anyway.

Best wishes

sceptic

Many thanks for that Sceptic - I have emailed Peter
and asked if there is any in the uk; or how to make some.

Just about to use some carp in the spring so it may just
come in time - Many thanks! Much appreciated.

jt.

You are going to have to invest in a product called Sonar. Also it might help to also invest in a pond aerator.