Cloudy Water

[billy0952]

I have a 20 ft Intex AGP. I let the water go green during the winter. Two weeks ago I slammed it, easily killing the algae and passing the OCLT test by the second night. There was a lot of dead algae on the bottom and also, I assume, suspended. I've vacuumed most of it out and have been running the sand filter, backwashing as necessary, pretty much continuously for nearly two weeks now. My water looks clear, but cloudy. I can see down about halfway to the bottom but it's too cloudy to see the bottom. I don't see any improvement from day to day.

My CYA is 50 and I've been keeping FAC between 3 and 6.
My TAC number matches the FAC number.
CH is low (100) but I don't care as it's a vinyl pool.
TA is 90
ph remains in range, 7.4
copper and iron are 0
Total dissolved solids is 900
The only outlier is phosphates which measures 200 with Leslie's saying it should be below 100.

I've tried 5 oz of PHOS Free poured directly into the skimmer and don't see any improvement.

Prior to that I've done several "Ultra Bright" treatments, all to no avail.

I'm thinking the next thing to try might be to see if any neighbors have a cartridge type filter they aren't using and run that a few days in place of the sand filter because that type, per TFP, filters out smaller stuff.

Any suggestions/recommendations/ideas? Help please!

Oh by the way, this winter I will treat the water with the polyquat stuff so as to hopefully prevent the water from going green over the winter.

 

[Texas Splash]

Good morning Billy. After reading your notes, we have to say you haven't really followed the TFP "SLAM" guidance (link below in my sig). A SLAM can easily take several days, and you must pass all 3 SLAM criteria before lowering your FC level. Because your CYA is 50, your SLAM FC level is "20". In addition, you're relying on pool store testing and expensive products that have proven to not be reliable. If you really want to take control of that pool and fix the water, here's a quick outline:
1 - Stop going to the pool store. You're wasting lots of money and getting bad testing & advice.
2 - Order your own TF-100 test kit (link below). It has all the reagents you need for accurate testing to get you through the season. Since you have algae, I would recommend the XL option because you'll need to run more tests.
3 - Stop adding various pool store products to the water. Often times those products can add side effects you don't need. The only two products you will need in the near future are regular bleach (aka chlorine) and perhaps some muriatic acid. But don't add any until you have the TF-100 test kit.
4 - Read the SLAM procedures (link below). You can't start a SLAM until you have the TF-100, but at least know in advance what is required.
5 - Depending on what your TF-100 test results tell us, a partial water change may be a good option for you as well since your pool is not too terribly large and/or due to the various pool store products you've added. But we need those accurate tests first.

You can manage your pool easily by obtaining the right test kit and staying away from the pool store who's main purpose is to earn revenue. We can help you break away from that.

 

[billy0952]

I have the Taylor K-2006 test kit and rely on the results I get from that. At the same time, occasionally I let the pool store test a sample and they've always, over the last three years, come up with results very close to my own results.

I slammed at a level of 20 for two days and the second night the chlorine level remained within spec, dropping very little. Over the last week or more I've been checking my chlorine level twice daily. I start out with it at 6 and it drops to about 2.5 during the day. I bring it back up to 6 in the evening and it stays around that figure over night.

I'll have to research the TF-100 kit to see what it has that the K-2006 doesn't.

You say I have algae. I don't understand that if I pass the overnight test, and have passed it every night over the last week or so. My water looks a normal color. It's not green, yellow or gray. It's clear for about 2 foot, then gradually gets cloudy so that I can't see the bottom clearly (48").

I use chlorine, 10% strength, which I get from Wal-Mart.

I'm thinking my sand filter is not doing as good a job as it should. I welcome any input/advice. I'll do some more testing this evening and report what I find.

 

[jeffchap]

If your water is cloudy, you have not completed your SLAM. One of the three criteria is clear water. You need to continue the SLAM until the cloudiness is gone.

 

[Texas Splash]

Since you clarified that you have the K-2006, three's no need to get the TF-100. Just use and post numbers from that in the future which is much better. A daily FC consumption of about 2.5 is good, and if you've pass the OCLT then you may indeed be struggling with a filtration issue. Have you deep cleaned your sand recently? What about adding a small amount of DE to the filter? One of both of those may help.
Pool School - Add DE to a Sand Filter
Deep Cleaning a Sand Filter

But also keep this in mind.....

I slammed at a level of 20 for two days and the second night the chlorine level remained within spec, dropping very little. Over the last week or more I've been checking my chlorine level twice daily. I start out with it at 6 and it drops to about 2.5 during the day. I bring it back up to 6 in the evening and it stays around that figure over night.

A 2-day SLAM is very quick. You also noted that your FC falls between 3 and 6. The absolute minimum FC for your CYA is 4, so the cloudiness you are seeing may still be indicative of residual algae. While the OCLT is a great tool, it's not all-inclusive which is why we have the 3 SLAM criteria.

 

[billy0952]

Thanks for the reply. Yes, I was amazed at how quickly the green algae turned to grey. I added the chlorine maybe 4 pm one afternoon and it had turned to grey by 7 pm that evening. I lost chlorine level during the first night but kept up the slam, checking the chlorine level every few hours on the second day. The grey went away by the afternoon and I was losing very little chlorine level at that time. I passed the OCLT test the second night. However, there was a ton of dead stuff on the floor of the pool. I was vacuuming it up with a battery vac which was time consuming as I had to clean out the filter every one or two minutes, a frustrating proposition. I ordered the hose to attach the vac to my skimmer and it arrived yesterday. I vac'd to waste and got out a lot of dead leaves and other mess. I'm going to vac to waste again in a few minutes as I see a dark spot near the center where I'm sure a pool of crud has accumulated due to the water circulation.

I did the deep clean to the sand filter a few days ago and I added sand to top it off at the high end of the recommended range as it had been at the low end ever since I first filled it with a 50 lb bag of sand.

I may try adding DE to the filter as you suggested if I don't see any improvement over night after another good vacuum cleaning.

It could be that I still have a lot of dead stuff on the bottom and I'm just circulating it while the filter is only able to remove so much between back washings.

I'll get there. I'm determined.

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If your water is cloudy, you have not completed your SLAM. One of the three criteria is clear water. You need to continue the SLAM until the cloudiness is gone.

I didn't think of that and you may be right. I've been relying on the chlorine level not dropping overnight to determine if I've completed it (slam). I'm going to vacuum to waste and then raise the chlorine level to 20 again and see what it looks like in the morning.

 

[Camp Pool Guy]

Billy,

I used to have this a bit (I have tandem filters) when I'm just on my sand filter (which is now rare due to water change req.). I determined (and it makes a WORLD of difference) that I can add a small amount of my regular media (I use Fiber Clear in my DE filter) to the sand filter after backwash and get water as clean as from my DE. Particularly i'm finding it helps keep the pool sparkling as once i'm fully up and running (for memorial day (commercial pool) it keeps me ahead of small particulate.

You might try that. You have the sand filter, for very low recurring money, you can make it behave like a DE.

Caveat: It does mean backwashing my sand filter much more frequently, but that is a small price given that i'm using only a 10th (or less) of the media in the sand filter that I use in the DE filter. So its 'usually' about 10 days for a DE backwash and 3-4 for a Sand . . . and both filters are giving the same 'result' water.

 

[billy0952]

If your water is cloudy, you have not completed your SLAM. One of the three criteria is clear water. You need to continue the SLAM until the cloudiness is gone.

This seems to be the issue. I did not complete the SLAM. I've resumed it yesterday and the water appears to be clearing up nicely. I expect by tomorrow morning it will be clear, or nearly so. I will keep it up 'till it is clear. Hopefully my grand kids will be swimming this weekend.

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Thanks to everyone who replied in this thread. This is a great, friendly forum and will save members time/effort/money if we will just trust, and follow good advice on here.