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Can a UV Lamp Really Remove / Inhabit Algae

04/04/2012 11:08 AM

Due to some reasons, my aquarium cannot be covered and must allow light to pass from top.

Some manufacturers of submersible UV lamp claim their product can killed bacterial, as well as algae. Is that true?

Anyone knows?

Thanks

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#1

Re: Can UV lamp really remove / inhabit algae

04/04/2012 11:22 AM

UV is used in water treatment, but obviously you would need to pump the water through a UV sterilising system not just bung a lamp into the aquarium and prob' kill the fish.
Google 'UV water treatment'
Del

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#2
In reply to #1

Re: Can UV lamp really remove / inhabit algae

04/04/2012 11:33 AM

OK Smarty Pants,

How does a Uv lamp inhabit algae?

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#5
In reply to #2

Re: Can UV lamp really remove / inhabit algae

04/04/2012 12:57 PM

You stick it up your.... <help I'm being dragged off by a moderator>.
I dunno I'm just trying to be helpful, and I don't think I've given a bum steer. I'm suggesting he research it himself.
I'm gonna tell this guy of you
.. an' maybe Mrs Cat too, then you'll be sorry...
her hard stare can cut through conrete.
Del
(PS I'm glad you like my trousers)

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#3

Re: Can a UV Lamp Really Remove / Inhabit Algae

04/04/2012 11:39 AM

Ultraviolet sterilizers are often used in aquaria and ponds to help control unwanted microorganisms in the water. Continuous sterilization of the water neutralizes single-cell algae and thereby increases water clarity. UV radiation also ensures that exposed pathogens cannot reproduce, thus decreasing the likelihood of a disease outbreak in an aquarium.

Aquarium and pond sterilizers are typically small, with fittings for tubing that allows the water to flow through the sterilizer on its way to or from a separate external filter. Within the sterilizer, water flows near to the ultraviolet light source, usually through a baffle system that lengthens the time during which the water is exposed to the radiation.

-From Ultraviolet Germicidal Irradiation wiki

Based on this, you'd have to have a separate filter, not just a lamp beaming down on your poor defenseless fish.

Here's an example of such a filter you could buy for your aquarium:
http://www.marinedepot.com/uv_ultraviolet_sterilizers_ozonizers_aqua_uv-ap.html

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#4

Re: Can a UV Lamp Really Remove / Inhabit Algae

04/04/2012 12:12 PM

UV removes nothing, UV can kill off pathogens but the remains..........remain.

http://www.xenoncorp.com/

This has pretty good info at one time. They have whats called a flash UV, very intensive.

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#6

Re: Can a UV Lamp Really Remove / Inhabit Algae

04/04/2012 2:49 PM

UV will kill you if it's strong enough. That is the cause of sunburn. So yes it will kill algae. Wouldn't recommend the submersible type for an aquarium. Those that are placed exterior to the tank in the filter system would be better. The algae kill in the tank may cause toxic problems to the fish if we are talking about a tank that heavy with growth. Not only that some fish my be more sensitive then other to the amount of UV in their environment. That way the filter has a chance to clean some of it up.

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#7

Re: Can a UV Lamp Really Remove / Inhabit Algae

04/04/2012 5:28 PM

Depending on intensity the UV is good for pathogens. It may also kill some algae.

HOWEVER, in our water treatment plants we have to remove the UV lamps periodically to remove the algae. Apparently 24 hour per day light source supports growth of these plants. (Think about it, where do plants and algae dervice their energy from normally.)

These lamps operate at levels that are unsafe for human exposure, even through 3m of water and 3m of air space. Shielding necessary!!

I think the "salesmen" are overselling their items and you will be dissappointed.

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#8

Re: Can a UV Lamp Really Remove / Inhabit Algae

04/04/2012 11:05 PM

UV can be used to control algae. Something you will need to know is the UV transmittance of the water so you can apply the correct dose of UV. Algae will require much more than normal bacterial sterilization. The minimum dosage required for water disinfection is 40,000 micro Watts sec/cm squared. UV dosage is calculated by multiplying the intensity of the UV x the time in seconds. The dosage required for algae control is about 400,000 mWsec/cm2. What that means is that you would either have to use multiple UV units in parallel or slow the flow of water through the UV unit to accomplish 10 times the dosage.

An alternative or combination of treatment that will work to control algae is to pump the water through a UV system to include 1 micron filtration and add hydrogen peroxide to the aquarium water. The dosage of peroxide will need to range from about 20 mg/L minimum to about 100 mg/L maximum. There are cheap test strips to help you maintain that dosage and it will take time to familiarize yourself. The peroxide does not harm the fish and the UV will form some radicals as the same water passes through a UV light. The radicals will perish very quickly. I have run swimming pools with that type of system but used mother nature's UV as provided by the sun. Worked great. I would advise using a combination system to control algae. As a side the peroxide H2O2 decomposes to water plus oxygen. The fish love it.

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#9

Re: Can a UV Lamp Really Remove / Inhabit Algae

04/05/2012 4:17 AM

Yes, but the water must circulate past the lamp.

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#10

Re: Can a UV Lamp Really Remove / Inhabit Algae

04/05/2012 5:08 PM

algae will grow rampent in direct sunlight or illumination that mimics sunlight. filters won't have much effect. close a curtain on bright days and change the bulb with a one with a narrow spectrum, such as a household bulb.

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#11

Re: Can a UV Lamp Really Remove / Inhabit Algae

04/05/2012 7:00 PM

UV for a fish tank is a waste of money if you plan to use it to keep algae growth down.
In a fish tank the algae grows on the surfaces of the tank. Some does circulate but most is stationary. You can not put the light into the body of the tank with out killing the fish at the dose needed to kill the algae.

They are a great idea for killing pathogens. The light is in the filtering system then, not in the body of the tank.

IF you have an algae problem you have too many nutrients in the tank. Feed less and do more water change outs. You may also have old lights giving out a poor spectrum. Most quality aquarium lamps are only good for one year.

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