3 weeks after SLAM completion...

Aug 20, 2020
18
Overland Park, KS
Directly after completing my SLAM treatment, due to a bad algae outbreak, the results were astonishing. Definitely the clearest water my pool has ever had in my 3 years of ownership, and maybe the clearest water I'd ever seen in any pool.

3 weeks later, I find myself noticing a degradation in terms of clarity and I want that back, badly. Since completing my SLAM, my chlorine has dipped just under the FC range to 3, for just a few hours before I got it back up into range (I test daily, sometimes twice), but other than that I'm curious what I can do to restore perfection. And, is it reasonable to expect this?

Most recent results: FC 7.6, pH 7.6, Alk 90, CYA 45

Regular maintenance:
• empty skimmer basket daily
• brush pool twice a week
• backwash once per week
• empty filter basket once per week
 

jseyfert3

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Oct 20, 2017
1,343
Southern WI
Pool Size
15000
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3 weeks later, I find myself noticing a degradation in terms of clarity and I want that back, badly. Since completing my SLAM, my chlorine has dipped just under the FC range to 3, for just a few hours before I got it back up into range (I test daily, sometimes twice), but other than that I'm curious what I can do to restore perfection. And, is it reasonable to expect this?
Absolutely is is reasonable to expect this. Cloudy water is usually a sign of something off chemically. You dipped under the minimum FC. As mknauss said, we round up the CYA to the nearest multiple of ten if the test shows it in-between multiples of ten, so you should target 6-8 and never, ever let it drop below 4. In other words, if you do your daily testing and it reads 5 ppm, add enough chlorine to target 8 ppm, don't wait for it to drop to 4 to add more chlorine. You don't want to always be dipping down to the minimum mark before adding more chlorine. And don't be afraid of going higher if needed, it's safe to swim up to the SLAM level, which is 20 for your CYA of 50. Got a pool party coming? Take it up to 20 (SLAM level) before the party starts, and let it drift back down to the target range. Going to get a thunderstorm coming that will wash a lot of debris or leaves into the pool? Take it up to SLAM level before the storm. Leaving for a few days and can't test the pool? Take it up to SLAM level before leaving. Doing these helps ensure it won't drop below minimum FC level.

In general though, testing and maintaining at the target range of FC should result in crystal clear water.
 
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Aug 20, 2020
18
Overland Park, KS
Very helpful @jseyfert3 . Considering my current situation and desires, should I just ensure I maintain the proper range (6-8 ppm) and allow it to slowly get better. Or, should I just elevate back up to SLAM level for a quicker result? - And, will that first option even get me back to that clarity I desire?
 

mickey4paws

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Apr 10, 2009
725
S.E. MI
Regular maintenance:
• backwash once per week
Hi Bradley,

I see you are backwashing once a week as part of your general maintenance. It's recommended that you only backwash when it's needed, which you can tell by looking at your gage on your sand filter. If it rises 25% or more above clean pressure, then backwash and rinse. If you backwash when it's not needed, the sand filter may not filter as well and it could lead to cloudy water. My clean pressure is 18 psi and when it goes 5 psi over that, I backwash.
 
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duraleigh

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Apr 1, 2007
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Sebring, Florida
Actually, 24/7 is a good answer. I was checking to make sure you were running your pump long enough for adequate filtration and at 24/7, obviously you are.

So, now, what is causing your cloudiness? I don't know but there should be nothing in your pool water that your filter can't get rid of unless the filter is not operating properly. No real reason to suspect it is broken. right?

I think I would try two things prior to considering a SLAM.....
1. Add just a little DE to your sand filter.....enough to get about a 1 psi rise on your gauge. Don't backwash you sand filter until you get a 25% rise in psi.

2. With a one-time dose, double your FC level. If you have any organics sneaking back into your pool that should get rid of them.
 
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Reactions: poolnoobgrandma
Aug 20, 2020
18
Overland Park, KS
Actually, 24/7 is a good answer. I was checking to make sure you were running your pump long enough for adequate filtration and at 24/7, obviously you are.

So, now, what is causing your cloudiness? I don't know but there should be nothing in your pool water that your filter can't get rid of unless the filter is not operating properly. No real reason to suspect it is broken. right?

I think I would try two things prior to considering a SLAM.....
1. Add just a little DE to your sand filter.....enough to get about a 1 psi rise on your gauge. Don't backwash you sand filter until you get a 25% rise in psi.

2. With a one-time dose, double your FC level. If you have any organics sneaking back into your pool that should get rid of them.
Thanks. I don't have any reason to suspect it's not operating properly. After all, I did my first SLAM about 3-4 weeks back and had great results and I'm guessing a fully functional filter is a prerequisite. What is "DE?"
 

red-beard

Gold Supporter
May 27, 2019
666
Houston, TX
Bradley, algae is everywhere. When I pulled apart the pool hose on my old pool cleaner (Polaris 280), I found green algae under the nuts. It is lurking and waiting for you to let it grow. The only ways to reduce your chances of an outbreak are being religious on keep the FC in the range. And you can go the extra mile and look for any dead spots where algae can hide. For example: Pool nuts, pool cleaner, weir doors (on the skimmers), pool vacuum and hoses, etc.

pool nuts.jpg
 

DorsalSpine

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Jul 8, 2013
714
Columbus, Ohio
DE filters will filter to a much smaller particle size than a sand filter. Basically you are adding a little DE to improve the filtering capability of your sand filter. That's why you need to watch the filter pressure carefully. Your filter might need backwashed sooner than you expect since it is suddenly much more efficient.