Cloudy Water

[chrisandtim]

I am usually pretty good at resolving my pool issues but this year I am stuck. AG Pool opened early due to warm weather. It was green so I treated with liquid chlorine. It went away but I have cloudy water, which I cannot clear. I have a Taylor test kit & hear are my results:

FC: 14
CC: .2
CYA: 40 (but of course water is cloudy!)
pH: 7.2
TA: 100

Do not test for calcium hardness as I have a vinyl lined pool. I have backwashed filter. Sand is just a few years old. Strong pressure coming from return so pump & filter seem to be working well. I've been keeping chlorine level high but still have cloudy water. Also tried a clarifier and when that didn't work, tried a floc treatment that was supposed to drop everything to the bottom to vac to waste. Well, it is morning & it did not drop to bottom.

Any other ideas? I have run out of ideas - short of emptying & getting new water, which seems like a last resort. Do I just keep filter running & hope it will clear?

Any advice welcome. Thanks.

[aylad]

Hello, and welcome to the forum!!

First off, don't put anymore clarifier or floc into the pool. They have their place--but it's usually as a last resort and I don't think you're there yet. Go ahead and run a test for calcium hardness--you don't necessarily need it in a vinyl pool, but if your level is too high, it's one of the things that can cloud your water. What form of chlorine do you usually use? Do you have a pressure gauge on your filter? Is the pressure rising as your pump is running, and when you backwash do you see dirty water? How high are you letting the pressure go before you backwash? (Remember that a dirty filter will filter much better than a clean one--you only need to backwash when your pressure is 8-10psi over your "clean" pressure.) Do you see anything blowing back into the pool from your returns? What size pump and filter do you have?


There is another trick you can use with DE to help a sand filter work better--but let's start with the answers to the above questions before we go that route......if you don't have a working pressure gauge on your filter, your next step is to get one!!

[PoolDoc]

Hi Chris-n-Tim;

You're in Massachusetts . . . so I'm guessing you may have an above-ground?

A very, very common cause of problems like yours is that pools, and especially AG pools, are installed with big pumps and little filters, when what's really need are little pumps and big filters. The result is the big pump blows the sand out of the little filter, after a season or two. Since there's not much sand, and not much resistance, you'll get "strong pressure coming from return", but the water won't be well filtered. You can get by when all's well, but when you have a pool full of tiny dead algae particles, things don't go so well, because the big pump blows the little algae through the small amount of remaining sand in the little filter.

So . . . the way to test if this IS the problem is to add DE powder, like Janet mentioned . . . and then go watch a return. If you see white DE powder blowing back into the pool, that's your clue: your filter needs work. Actually, what probably is needed is to
1. add sand to the filter;
2. install a valve (or maybe, partially close an existing valve) to SLOW flow through the filter;
3. and look into swapping the impeller in your pump for a smaller one, so you can slow flow without wasting electricity.

If missing sand IS your problem, ironically, this can make clarifier and floc fail. Those products can (don't always, though) make little particles like algae clump together. But, if the (technical language alert!) "shear forces" are too high -- and they probably are in a big pump/little filter situation -- the clumps will be broken apart. Once that happens the floc / clarifier / dirt blend is ACTUALLY harder to filter, and now the floc or clarifier that's attached can make it HARDER to filter the stuff out.

Of course, there are other possibilities. But it would be a good idea to do the DE test, answer the questions Janet listed, and if you can, send pictures of your pool, pump, and filter to poolforum@gmail.com so we can see exactly what you've got.

Good luck.

[chrisandtim]

Thanks. I will test for calcium hardness - but typically mine is low not hard; but I will check.

There is a pressure gauge on the filter. I suspect it doesn't work as it never really changes, LOL. I've never bothered changing it. I've backwashed recently after vacuuming, basically after return flow gets low. When I backwash, there is dirty water that appears in the glass, then it clears - like normal. During a regular season I do not usually back wash very often. It's usually only during opening that I have to backwash more than normal.

Nothing seen coming from return into the pool. I use liquid chlorine - 12%. I usually just follow BBB method & my pool is normally crystal clear. I'm not one for adding a lot of stuff to it - except this time when I tried the clarifier & floc - will hold off on doing any more of that though.

Let's see....pump is I think 1.5 hp Hayward & filter size...not sure...will have to go back out & check. Not thrilled with the idea of messing with the impeller or filter as I have never had a problem before.

[PoolDoc]

Not thrilled with the idea of messing with the impeller or filter as I have never had a problem before.

Do the DE test, then. If your filter holds DE, it will also filter algae, eventually. With the floc-ed and clarified water, it will help if you can slow the flow down, however.

[chrisandtim]

Do I just put DE in the skimmer to do that test? Is there a way to buy a small bag of DE? I used to have a DE filter & all I remember are those large bags of it.