Cloudy pool 2+ weeks into SLAM despite passing OCLT and CC under 0.5

[Pool94]

I am two weeks into a SLAM to get my 26K gallon AG pool operational. I have seemingly tried everything under the sun to get my pool clear - it is currently a cloudy light blue and has not improved much over the last week (maybe 5% better in one week). If I look closely I can barely see my pool robot at the bottom.

• Deep cleaned sand filter
• Passed OCLT for over 1 week
• Using cellulose fiber to speed filtration (almost gone through 3lbs so far)
• CC is 0.5
• Pool robot is running several hours throughout day
• Multispeed pump running on high 24/7
• Backwashing when PSI increases ~25%
• FC has been kept at SLAM level for my given CYA
• Overall pool chemistry is good

I am stumped on why things aren't clearing up faster. At the current rate, I would estimate it could take another 4-6 weeks for clarity to reach an acceptable level. Here are my questions:

• Is it possible I have filtration issue that would requiring replacing the sand? When I deep cleaned the filter I saw no signs of channeling, but cannot confirm the quality of all the sand or how it was treated before I inherited the pool. I also don't see and cellulose fiber pass through my return when adding it, so I think my laterals are in good condition.
• Since I am passing OCLT and have a CC of ~0.5, do I still need to maintain FC at SLAM level? It's becoming really expensive keeping this up for 26K gallons for over 2 weeks now. I lose around 5ppm FC on average during the sunny part of the day, so am forced to add cal-hypo every day
• What exactly is the white cloudiness of the pool caused from? Dead algae? Some other matter floating around? Whatever it is, my filter doesn't seem to be catching it quickly. I manually scooped and had my pool robot remove a massive amount of leaves and other debris about 3 weeks ago, but I don't think this should be an issue now.
• Is it worth considering a clarifier or floc at this stage? I know TFP doesn't seem to approve of these products, but I am not having success following their SLAM method - and continuing to supply my pool with 1-2lbs of cal-hypo a day, and adding CYA as needed, is getting expensive, especially when progress is extremely slow. I would probably need 40-50lbs of shock to complete the SLAM (since I am technically not to supposed to stop SLAM until the water is clear)

Here's my current chemistry:

FC: ~12 - 14ppm
CC: 0.5
pH: 7.5 - 7.6
TA: 110
CH: 200
CYA: ~30 - 35

 

[littlebuddy12]

how bad was the pool when you started

 

[revitup]

Sounds like floc might be a consideration in this case. Can you vac to waste?

 

[Wobblerlorri]

I noticed you're using cal-hypo instead of liquid chlorine, which is what we recommend for the TFP method. It may be a long shot, but try ditching the cal-hypo and switch to liquid chlorine for the remainder of your SLAM. Can't hurt, might help.

Some other things to do to bring your SLAM into line:

1. Reduce your pH to 7.2
2. Switch to liquid chlorine
3. Check your FC at least three times a day and never let it drop below your target level
4. Scoop around the bottom of your pool to make sure all the debris is gone.

Worst case scenario, drain half your water then refill and rebalance for your SLAM. At least you'd be able to see the bottom.

 

[Pool94]

I noticed you're using cal-hypo instead of liquid chlorine, which is what we recommend for the TFP method. It may be a long shot, but try ditching the cal-hypo and switch to liquid chlorine for the remainder of your SLAM. Can't hurt, might help.

Some other things to do to bring your SLAM into line:

1. Reduce your pH to 7.2
2. Switch to liquid chlorine
3. Check your FC at least three times a day and never let it drop below your target level
4. Scoop around the bottom of your pool to make sure all the debris is gone.

Worst case scenario, drain half your water then refill and rebalance for your SLAM. At least you'd be able to see the bottom.

That was my thought too. Is it possible every time I was adding cal-hypo it was impacting the cloudiness, so I was pretty much running in circles? I tested my CH again this morning and it's around 300, which still seems like it would be fine to me. Does cal-hypo take a couple days to clear up after adding? If so, maybe I never gave the water enough time to clear. I'm hoping somehow I haven't permanently altered the clarity from the amount of cal-hypo added.

Also, I tested my pH again and I'm actually more around 7.2, not 7.5. If I switch to liquid chlorine or bleach how soon do you think I'd see an improvement?

I'm trying to avoid draining the pool as I'm worried about the liner shrinking. Maybe there is a way I could drain/refill at the same rate to avoid losing water?

I have 250lbs of fresh sand I could replace the old sand in my filter from (it's about 3 years old). Is this worth doing at this stage?

 

[Pool94]

how bad was the pool when you started

It was pretty much a swamp. I would have drained it, but I read on here that pools as large as mine it's not recommended. Especially since I would not be able to fill it quickly enough to avoid the liner shrinking.

 

[Wobblerlorri]

If it was a swamp, it might be worth changing out your sand, or at least doing a deep clean. Sand doesn't wear out, but it does get gommed up with organics over time. There's an article and I think a video on deep cleaning the sand filter on the site in Pool School.

You can do a drain and replace, where you're draining water at the same rate you add it. An article and/or video exists in Pool School, just like above.

The TFP method depends on adding ONLY what your pool needs. A vinyl liner doesn't need calcium, which is what you're adding with cal-hypo. Go to plain ol' liquid bleach asap, do a drain and replace, and clean your sand filter. That should set you up for a crystal clear pool in no time -- I'd say 2 weeks max!

 

[Pool94]

If it was a swamp, it might be worth changing out your sand, or at least doing a deep clean. Sand doesn't wear out, but it does get gommed up with organics over time. There's an article and I think a video on deep cleaning the sand filter on the site in Pool School.

You can do a drain and replace, where you're draining water at the same rate you add it. An article and/or video exists in Pool School, just like above.

The TFP method depends on adding ONLY what your pool needs. A vinyl liner doesn't need calcium, which is what you're adding with cal-hypo. Go to plain ol' liquid bleach asap, do a drain and replace, and clean your sand filter. That should set you up for a crystal clear pool in no time -- I'd say 2 weeks max!

Thanks for the advice!

I already performed a deep clean on my sand filter a couple weeks ago. I used a garden hose and shifted it around occasionally for about 3 hours - until the water coming out from the top was clear.

My pool has an isolated main drain, so about 30 minutes ago I set the filter to waste, turned the pump off, and am letting gravity push the water out - while simultaneously adding water back in with a garden hose. I roughly calculated the rate, and am removing water at 5GPM and adding it back also at 5GPM. So in theory, if I let this run for 3-4 days all my water would be replaced, while simultaneously not altering the water level. Does this sound like this method is okay? I would probably take a few breaks in between and set the pump back to filter and add chemicals back as needed.

I'm going to the store now to buy some 7.5% bleach chlorine and will begin using this instead of cal-hypo.

 

[littlebuddy12]

i use cal- hypo and my water doesnt get cloudy if it was the cal-hypo it shouldnt be cloudy for longer then a few hours

 

[PoolBrews]

Is it possible that the cellulose fiber got through the sand and is what is causing the cloudiness? I tried using a cellulose product, and this happened to me some time ago with a cartridge filter. It worked initially, but long term the cellulose broke down enough to go through the cartridge. Luckily, I caught it quickly, before a ton got in the water. I eventually cleaned it up using a new cartridge filter - the old one was ruined.

 

[Diamond_Pool]

I had a similar issue with cellulose fiber. It does go through sand filter in few days and causes cloudiness. I collected in simmer sock and I am quite confident this is cellulose fiber. It likely breaks down into single hairs and come out of filter eventually.
I slammed the pool twice thinking algae but addition of clarifier make pool go crystal clear overnight and I collect bunch of this junk.


I

 

[Jerry11]

Any solution to this issue. Seeing similar issue. Water is mostly clear but I cannot get that crystal clear water that my neighbors have. Tried SLAM and meet all criteria. I vaccum, brush regularly, run polaris 2+ hours a day. Clean DE filter and skimmers when needed.

FC: ~12 ppm
CC: 0.0
pH: 7.2
TA: 90
CH: 200
CYA: ~55