Algae, followed the SLAM criteria, here's what I've done and measured (timline), still blue & cloudy

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M

matthewbnntt

Member
Jul 20, 2020
10
Houston, Texas
Hi there TFP folks! Name's Matt, I'm a newbie (both here on the site and as a pool owner). I've lost faith in local pool store folks, they only appear to want to sell me chemicals (and lots of em!). I've been silently following the prescribed SLAM instructions on this site. I'm an engineer and in general, follow instructions and can reliably measure stuff when my eyesight cooperates! I'm sure to many of you, this is easy-peasy, but this is stumping me. Here's a time-line of what I've done and why
Starting in mid July had an algae problem.​
Shocked - did no good. Tested water at Pool store, long story short, CYA was WAY high (100+, but HTH strips showed into that 150-300 range)​
Drained out 1/4 of water (estimate) and filled back up (1st attempt to get CYA down)​
Decided to add in Pool Time Algicide MaxBlue (~4oz and after that settled down, some Pool Time Super Water Clarifier (1oz)). No real improvements, very cloudy water, kind of green-blue now. Convinced myself that CYA was still too high.​
Drained over 1/2 of pool and filled it back up. Acquired a DPD then a FAS-DPD Taylor kit.​
7/20 was when I drained out half the water and really started getting serious about elevated Cl levels, at first with DPD, but starting on 7/24 with a Taylor FAS-DPD kit.​
7/20 - Ph: 7.6, FC:4, TC:4, Alk:100, CYA:60 (Pool Store measure), Added 128 oz of 10% Bleach, per SLAM guidelines​
7/21 - Ph: 7.6, FC:10+, Alk:120 (DPD test), Added 56oz of 7.5% Bleach​
7/22 & 23 - added bleach, didn't record, but Cl levels eye-balled with DPD test​
7/24 - Ph: 7.6, FC:15 , CYA: 60 (FAS-DPD for Cl), Added 61oz of 7.5% Bl​
7/25 - FC:23 (FAS-DPD), no bleach added​
7/26- FC:20 (FAS-DPD), added 27oz of 7.5%​
7/27- FC:20 (FAS-DPD), added 27oz of 7.5%​
7/28- FC:21, CC: 0.5 (FAS-DPD), added 24oz of 7.5% (started tracking CC at this point using FAS-DPD)​
7/29- Morning FC:17, CC: 0.5 (FAS-DPD), added 50oz of 7.5%​
7/29 - Evening FC:20, CC: 0.5 (FAS-DPD), let it ride for an OCLT​
7/30 - Morning FC:18, CC:0.5 (FAS-DPD), added 40oz 7.5%​

Thanks for sticking with me. Here's my question. My pool went from the first image to the second image. It's been blue since the 7/23, but it is cloudy as heck. Can't see the bottom clearly. I've been cleaning the filter 2-3 times per day (SFX1000gph with a Type A cartridge) really well. I vacuum it often (every other day maybe) to try and pick up organic matter. I brush 1-2 times /day to stir things up and get em to my skimmer. Pump has been running 24/7.

How long do I have to wait for the cloudiness to clear up? My CC is down, I pass the OCLT test, The Cl level has been well maintained since 7/24 (but nice and elevated since 7/20 best I could tell with DPD test) Is this typical?

I love the learning this site offers and wanted to see what y'all thought. Any advice or suggestions appreciated.
 

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Hey Matt! Glad you’re here!
I have to point this out & hopefully it will help u along.
TheSLAM Process Is not a once a day add liquid chlorine thing.
It requires testing & adding liquid chlorine multiple times daily.
Every hour below slam level is an hour algae wins.
You must Shock Level And Maintain.
You must keep doing this until u pass all 3 end of slam criteria:
❌Crystal Clear Water
✅CC is .5 or lower
❌Pass an Overnight Chlorine Loss Test
You’re not quite done yet. Keep Slammin!
With the stock cartridge style filter for that pool it could take a while.
I suggest u try to vacuum to waste & help the filter out some.
 
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Mdragger, thank you very much for the feedback! Honestly, I thought once a day was good enough. 🥺

Would morning and just after sun goes down suffice? Whats the reasonable frequency of checking?

Also with the Taylor kit, can I use 5mL of water and count each drop as 1ppm (how much powder, just 1 scoop?).

How long is a while by the way? I bought some type A filters on amazon, but they not much different from the stock.

in any event, thank you very much for the perspective and advice, very much appreciated!
 
We usually suggest 3 or 4 times a day or more at the beginning since chlorine demand is usually high then - as it starts holding more u can back off some. Never more than once an hour.
At this point shoot for at least twice a day. I have a feeling this is why it has dragged on so long for u. U weren’t really hitting it. 1 step forward 2 steps back. If you’re running low on reagents order some now. Tftestkits.net has big ones & they ship fast. The 5 ml sample isn’t super accurate so definitely don’t use it for the oclt. It’s really only to get u through until your refills come. Swap out the filters as often as possible. You’re still losing chlorine overnight so your algae definitely isn’t dead yet. Don’t back off now.
Those filters suck- the sand upgrade is the way to go although I know its hard to find them right now.
Vacuuming to waste is your best hope now.
just create a siphon with the hose & throw it over the side.
 
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No not a drain. A side port vacuum or one you can attach to the skimmer and send to waste (you might not have a multiport valve though). @Mdragger88 will tell you if there's another option, I'm unsure. Vacuuming the debris and discharging it so it doesn't reenter your filter since that clogging can also slow you down especially with a cartridge filter.
 
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Vacuuming to waste is “wasting” the water.
if you don’t have a setting on your pump for that (I don’t think you do) then u can use a standard pool vac (head, hose,& pole) as a siphon vac
- Place vac in pool w/hose attached
- use jet to fill the hose until all the air is out(no more bubbles)
Or u can just slowly submerge the hose
- with the end of hose under water hold your hand over the end of the hose
(to prevent air from entering)
- then quickly bring the hose end over the side of the pool to the ground-
Now the water is being siphoned from the vac head to outside of the pool -
- vac deliberately/quickly but try not to disturb what’s on the bottom too much so as much of it gets vac’d out as possible.
* note* some find it helpful to Use a large clip or a rope to tie up the end of the hose so it stays where u want it during the process.
I always use this process to vac to waste so i can bypass my pump as it doesn’t waste as much water as the pump does.
heres some videos:
 
Mdragger88, thank you for the video! That's how I overboarded half of my water last time. I used the shop-vac hose that I have in the garage. Good to know that I can use that method to vacuum "to waste" as well, I hadn't thought about that! My current vacuuming setup is a garden hose variety (literally) that uses the venturi method. I've rigged it up so that I can use the return from my pump as the source (and not fill up my pool as I vacuum). It has a net that catches the gunk.

I've been busy after everything since your last posts, and I *think* I see progress in recent days!
We've had heavy rain this past week in Houston and the pool is uncovered, so I've had to overboard the water 3 times (not the whole pool, just to get it down so the skimmer isn't submerged). I've been maintaining the Cl levels all the while, activity brushing, testing (and I've got more R-0871 en route, but rationing until it arrives by using 5mL of H2O, 1 scoop of powder, so each drop of my R-0871 is 1ppm).

In addition, I had the pool store folks do a test as well (since I've been overboarding water during the rain). They say that CYA is down to 40, which means lower Cl to achieve SLAM! (however suspect their calcs are, it has to be down)

Test results last night and today;
7/30 Evening: Ph:7.5, FC:21, CC:0.5, Alk: 110, CYA:60 (was what I thought), so I added 40oz 7.5% to achieve 24
7/31 Morning: Ph:7.5, FC 23, CC:0.0, Alk: 110, CYA:40 (poolstore), new calc using PoolMath says let it ride down to 16, but I might just maintain at 20ppm (as a node to inaccuracy of pool store test on CYA, assume CYA is 50).

Changed the filter to a new one (I've been rotating between 2 filters so far this summer, but figured I'd use the last new one of the three I have to do this last bit of cleanup).

For the first time this morning while testing, I could actually see the bottom of the pool, albeit still cloudy, but nevertheless, that's progress!

Thanks again, I guess my expectations for the cloudiness to clear up are not in line with reality. That combined with my inaccurate Cl management early on (along with super high CYA caused by adding it inadvertently through Trichlor shock and pucks) resulted in the debacle I find myself in!

If it hasn't cleared up a lot more by next weekend, my wife and I have agreed to overboard and start again (we have kids that desperately want to swim :) ), but I hope that doesn't happen!!

Thanks again!
Sinc,
Matt
 
mknauss, I don't have a CYA test kit. I rely on a combination pool store tests and HTH strips. It seems like it's tuned in pretty ok now, but before July, it was registering WAY high on the HTH strips. Pool store measurements where totally off early on. Given that CYA levels won't change unless I add it or overboard water, I've relied on the combination of the two measurements methods above (and I don't add it anymore using 7.5% Sodium Hypochlorite as my Cl source). I read that article you referenced, thank you.
 

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Accuracy, as they say, is in the eye of the beer holder 😉

I think flying blind is a little extreme, isn’t it? I have an hth strip that suggests 40-50 is about right, backed up with several pool store tests suggesting the same range (3 times). If I err on the high side wrt to NaHypo and CYA assumptions, how am I flying blind?

Not trying to be snarky, honest question.
 
TFP is based on accurate, reliable, pool owner testing. The incidences of grossly inaccurate pool store test results and down right false test strip data lead us to never rely on that data. So you are welcome to follow it, use it, etc. But we will not provide guidance on it.
 
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Friend of mine with a pool had an old black dot test (no titration) where you mix pool water with solution and push the stick down until you can’t see it. I’m not confident of the accuracy, but it was in between 40-50, but the scale isn’t linear, so guesstimate 45 for CYA. Pretty close to pool store test!

I can’t find a titration kit for CYA, only thing I can find are strips and black dot tests, is there one around that folks prefer?
 
Clarifier will just gum up your already overwhelmed filter.
if you haven’t passed anOvernight Chlorine Loss Test
You haven’t killed all your algae & it will just return even if it does help although it usually just makes things worse.
The most accurate cya test is the “black dot” test
CYA (Cyanuric Acid) Test (all tf test kits use Taylor reagents)

if you’re reading above 40 then your cya is 50ppm so your Slam fc level is 20.
Maintain that until u pass all the end of SLAM Process criteria. No shortcuts 😊
 
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Thanks for all the help Mdragger88, Mknauss, & batesjer!

Happy to report that yesterday morning, I passed an OCLT (holding a 23ppm FC level from the night before), pool has been very clear and less than 0.5ppm of CC (the FAS-DPD test for CC turned super slight/clear pink (barely pink at all really) and then 1 drop of R-003, clear as a bell. Using a 10mL sample of water).

Looking forward to getting back in the pool (once the FC levels drop down to something a bit more comfortable)!

Have plenty of the R-0871 reagent now, so will likely do the 25mL sample to test more accurately for FC and CC on an additional OCLT this evening and tomorrow morning (just to ensure that my SLAM is done).
 
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