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Pool Water Chemical Mixture

07/08/2011 5:47 PM

Here is a water chemistry question from a non-chemist pool owner. My pool pump only circulates the pool contents for eight hours a day normally starting at 0900. We had a hell of a storm yesterday and two inches of rain water got dumped into my pool, naturally after I had just added water lost from evaporation and shocked the pool with three jugs of chlorine. So now I need to pump out the extra water. The question for you folks is this, with the pool water standing stagnant over night do the chemicals in the pool water settle to the lower layers of the pool volume, or rise to the upper layers, or just stay mixed? You know kinda like salinity layers submarines use to hide from surface SONAR. What I am getting at, is should I wait for my pump to circulate the water for a while before to mix everything up before pumping it out since I'm gonna lose anyway? If the chemicals settle to the bottom, I could shut off my main drain located at the bottom and use the skimmer to remove the water from the top. Or if they are at the top, shut off the skimmer and use the bottom drain. Does any of this make sense? Chemicals are pretty freaking pricey these days as pool owners know. So folks, what do you smart people say?

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#1

Re: Pool water chemical mixture

07/08/2011 6:07 PM

Pump it down to the desired level.

Pool chemicals don't stratify. If any stratification occurs at all it's more a dissolved solids settling than chemical separation.

Or if it isn't affecting the skimmer, just let it evaporate.

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#4
In reply to #1

Re: Pool water chemical mixture

07/08/2011 7:25 PM

Just to clarify, pool chemicals do stratify, but this is down to water temperatures and the location of inlet nozzles and outlets. Two inches of rain would not lead to stratification. In fact (assuming the rain is colder than the pool water, which I would hope) it should mix rather well.

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#5
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Re: Pool water chemical mixture

07/08/2011 7:31 PM

Just trying to keep it simple.

Remember, he's not a chemist and the water gets circulated every 16 hours.

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#6
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Re: Pool water chemical mixture

07/08/2011 7:46 PM

Yes, you are quite right. I probably should not have stuck my oar in! Just a bit of nit-picking about stratification, but I think we agree that heavy rain would not lead to this.

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#7
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Re: Pool water chemical mixture

07/08/2011 7:57 PM

Your comments are always welcome.

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#8
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Re: Pool water chemical mixture

07/08/2011 8:06 PM

Thanks.

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#2

Re: Pool water chemical mixture

07/08/2011 6:11 PM

Even though solution density is higher than water, affraid hypochlorious acid formed when you add chlorine to pool water is too soluble to expect any depth dependent concentration difference. (If it was stirred or had enough time to disolve that is) S.M.

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#3

Re: Pool water chemical mixture

07/08/2011 6:42 PM

I too am from Central Florida...some storm ! I will be emptying water from my pool this evening as well. As the others have pointed out, no need to mix. Just remember to add some pool stabilizer as you are pumping that out as well (if you stabilize your pool).

Incidentally, I was a Surface Ship Sonar Technician in the Navy. We just let them think they can hide.

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#12
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Re: Pool water chemical mixture

07/09/2011 8:47 PM

I think we hid more than you think <VBG>. There are boats and there are targets.

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#18
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Re: Pool water chemical mixture

07/10/2011 12:18 PM

Bottom Bounce Track/ODT baby...crack those pressure hulls.

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#9

Re: Pool water chemical mixture

07/08/2011 8:54 PM

I have a pool without circulation pump. Every 2 days I use some water of it to sprinkle the lawns and refill from a well. I have no filter installed but use the ground as a natural filter (% back to the well) When the water troubles (misty) I add some muriatic acid and when algae tend to show some chlorine pellets. These sink to the bottom until they dissolve. The grass is St- Augustine and likes the little chlorine from the pool water.

I used to use color strips (reactants), but the water composition is always OK this way.

Just a little lime.

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#10

Re: Pool Water Chemical Mixture

07/09/2011 9:50 AM

Frankly I suggest you do nothing at all. If you really wanted to mix the chemicals, I have no doubt you have a manual override on the pump timeswithch, or just advance the clock temporarily. Why do you even need to drain off 2" of water? Sounds like a lot of fuss about nothing.

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#11
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Re: Pool Water Chemical Mixture

07/09/2011 8:45 PM

Actually what happens when I get too much water in the pool (above my marked high water mark in my skimmer) the float ring in the skimmer will float up and get cocked, then jam in the basket. When this happens, water doesn't flow down the skimmer and creates a kind of waterfall, and the pump starts sucking air. Normally what I do to alleviate this until I pump it down, is drop part of a paver stone in the basket to weight it down on its seat. I have it in there now and it keeps the pump from cavitating and starving. Years ago this happened while I was out of town, the wife paid no attention, the pump ran for a few hours not pumping and it melted some of my discharge piping and the impeller. That kind of stuff is always a big pain in the butt.

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#13

Re: Pool Water Chemical Mixture

07/09/2011 8:50 PM

Thanks to all for the good info. I now understand that it makes no difference when or how I pump the pool; I'm gonna lose chemicals.

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#14
In reply to #13

Re: Pool Water Chemical Mixture

07/10/2011 3:22 AM

One little trick if you have a skimmer box is to install an overflow at the high water point in the skimmer box.

This way, when the rains come - assuming the pump is not running - the rain will flow out the overflow taking minimal chemicals with it.

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#15

Re: Pool Water Chemical Mixture

07/10/2011 3:37 AM

All of the above have provided good clues about what has happened to your pool water. You're going to lose about more than about 5% of your chemical load if the pool is, say, normally at a 3 foot depth. Here in NC, rainfall can be quite acid as it probably is in FL, and you likely need to be concerned mainly with adding enough rather inexpensive sodium carbonate to regain a higher pH. Good luck.

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#16

Re: Pool Water Chemical Mixture

07/10/2011 9:17 AM

Take a simple test. Measure your chlorine level with your Test Kit.Take water sample from top surface and see test result, then water sample from mid level and see test result then finally water from pool bottom for result. There you have your solution where to throw out .

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#17

Re: Pool Water Chemical Mixture

07/10/2011 11:20 AM

Re: Chemicals are pretty freaking pricey these days .

Years ago a buddy of mine had a in-ground pool and was always complaining about what it cost him for chemicals per month. Wanting the water temp. a little warmer and not being able to afford a heater, someone suggested one of those bubble pool covers and suggested it would help warm the water on sunny days and at night would help keep some of the warmth in.

It worked really good but the greatest thing of all is he found out the cover also saved him about 1/3 of his chemical costs due to less evaporation of the water. It saved a little electricity too as the pool required less water put in each month also.

He was amazed that something so simple saved so much.

Rescue

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#19
In reply to #17

Re: Pool Water Chemical Mixture

07/13/2011 6:38 PM

We used to have one of those bubble pool covers but it was a pain to mess with (get in and out of the pool, then store it); it came with or solar heater installation. We had one of those on our spa up in SC to help keep the temp up in the winter. One day, as luck would have it when I was on the deck, my cat decided to take a short cut accross the spa cover. She immediately sank in it and was engulfed. I was able to pull her out with the cover. This same thing can happen to an unattended child or other idiot. Did you watch the first Lethal Weapon movie when they shot the druggie and he fell into the pool? Well there you go.

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