My chemicals are a mess (and white build-up on SWG)

[ColoradoPool2022]

I'm on my third season with the pool and this summer has been a trial on my patience. The main indicator that there is an issue is that for the last two summers I've had white flakes showing up in the pool below the returns. It is coming from build-up on the SWG. I spray it off with a hose and try to get at it with a popsicle stick (trying to avoid too much acid washing of the SWG) but it keeps coming back. I posted something about it here last year and no luck on a solution. Then, this winter while the pool was closed and just the hot tub running, I took the Alkalinity down to about 70-80 and that did the trick. No flakes all winter. This spring, we opened the pool and after about two weeks, the flakes showed up again. I reduced the alkalinity to 70-80 (using the acid and aeration method) and acid washed the SWG. The flakes went away for another couple weeks and returned (and my alkalinity went back up to near 100). I repeated the alkalinity reduction process, flakes stopped for a bit and then returned.

Note that I've eliminated adding ANY chemicals other than small amounts of fill water for at least the last 6 weeks. I used to have a weekly regimen of GLB Natural Clear Clarifier (for all the oils that would gather on the surface), GLB Sequa-Sol (for scaling; lot of good that did) and GLB Super Blue (to keep that water looking new). And I would HTH Cal-Hypo (56%) following pool parties with lots of kids and after an algae outbreak last year (see note below on calcium levels; I'd bet I've added around 15 lbs of this over the last two seasons but stopped this past June after learning that it could increase the calcium level).

So I've been paying closer attention to all of my chemicals and seeing significant volatility. My last two readings are at the bottom of the thread and you can see the volatility but here are my observations:
- I use the Taylor test kits/chemicals.
- My Alkalinity keeps going up for some reason. Today it is at 90, 3 weeks ago it was at 70. This increasing has happened twice this summer. My fill water is 60-70 and I add maybe a couple hundred gallons every 7-10 days. Why is this happening? Note that I've had no issues maintaining Ph in the 7.3-7.6 range.
- My calcium seems really high. I've gotten various results throughout the summer (I think mostly user error) but I'm pretty confident in today's reading of about 620. I've seen other threads that say this is fine. My belief is that this is the primary source of my issues and plan to replace about 50% of the water after this weekend (my fill water is about 60-70). I am making the total guess here that the high calcium is having some sort of chemical reaction with my construction materials and other chemicals driving all else out of whack. How much does the HTH cal-hypo increase your CH?
- My salt spiked a couple weeks ago at 4000 (I haven't added salt in about 8 weeks) and today it was down to 3000.
- My CYA keeps dropping for some reason. I've added about 5 lbs of granules this summer
- I believe my finish is discoloring for some reason. See the first pic attached of our sun deck. You can see this on the right. This is the main spot it is happening.
- The "shade" of the water appears more aqua-marine than I remember when we opened it the first time 3 seasons ago. I do not believe I have algae as there are no visible signs and I am passing the overnight chlorine test.

As I said, my next plan of action is to replace 50% of the water and hopefully get the calcium right. Then address the Ph, salt and alkalinity (in that order). Any thoughts are appreciated!

8/28 and 8/16, respectively, chemicals:
FC- 4.5; and 6.5 (the latter reading is because I had left the SWG turned up while out of town)
CC- 0; and 0
Ph- 7.6; and 7.6
TA- 90; and 86 (it was 70 on 8/8)
CH- 620; and 460 (the latter may have been a misread)
CYA- 40; and 55
Salt- 3,000; and 4,000
Temp- 83; and 78
CSI- +0.20; and -0.07 (most of the summer my CSI has been about -0.20 to -0.30)

 

[PoolStored]

First, stop adding all the GLB products. They are unnecessary.

I would ask, before you decide to do anything else, STOP, and do a careful full panel of tests.
Clean the vial with rubbing alcohol, dry and do a full panel. Take your time. Reagents vertical, let the drops form and drop under their own weight. FC, CC, pH, TA, CH, CYA.
Clean the vial with ammonia, dry, then do the SALT test.

Water Testing Errors - Further Reading

www.troublefreepool.com

Extended Test Kit Directions Archives

www.troublefreepool.com

- My Alkalinity keeps going up for some reason. Today it is at 90, 3 weeks ago it was at 70. This increasing has happened twice this summer. My fill water is 60-70 and I add maybe a couple hundred gallons every 7-10 days. Why is this happening? Note that I've had no issues maintaining Ph in the 7.3-7.6 range.

I think this is testing error. Clean the vials often. When you do the TA test add drops until color does not change and subtract the last drop. How did you get a TA of 86?

- My calcium seems really high. I've gotten various results throughout the summer (I think mostly user error) but I'm pretty confident in today's reading of about 620. I've seen other threads that say this is fine. My belief is that this is the primary source of my issues and plan to replace about 50% of the water after this weekend (my fill water is about 60-70). I am making the total guess here that the high calcium is having some sort of chemical reaction with my construction materials and other chemicals driving all else out of whack. How much does the HTH cal-hypo increase your CH?

Test your fill water CH. Might also be testing errors. When you do the CH test add drops until color does not change and subtract the last drop.

- My salt spiked a couple weeks ago at 4000 (I haven't added salt in about 8 weeks) and today it was down to 3000.

Clean your test vial with ammonia before and after testing salt.

- My CYA keeps dropping for some reason. I've added about 5 lbs of granules this summer

CYA drops 5-10 a month in the summer. If your water temperature is above 90, you might see drops up to 15.

- I believe my finish is discoloring for some reason. See the first pic attached of our sun deck. You can see this on the right. This is the main spot it is happening.

Can you post a close up?

- The "shade" of the water appears more aqua-marine than I remember when we opened it the first time 3 seasons ago. I do not believe I have algae as there are no visible signs and I am passing the overnight chlorine test.

As I said, my next plan of action is to replace 50% of the water and hopefully get the calcium right. Then address the Ph, salt and alkalinity (in that order). Any thoughts are appreciated!

Before you do anything, get a full accurate panel and post the results.

 

[ColoradoPool2022]

First, stop adding all the GLB products. They are unnecessary.

I would ask, before you decide to do anything else, STOP, and do a careful full panel of tests.
Clean the vial with rubbing alcohol, dry and do a full panel. Take your time. Reagents vertical, let the drops form and drop under their own weight. FC, CC, pH, TA, CH, CYA.
Clean the vial with ammonia, dry, then do the SALT test.

Water Testing Errors - Further Reading

www.troublefreepool.com

Extended Test Kit Directions Archives

www.troublefreepool.com

I think this is testing error. Clean the vials often. When you do the TA test add drops until color does not change and subtract the last drop. How did you get a TA of 86?

Test your fill water CH. Might also be testing errors. When you do the CH test add drops until color does not change and subtract the last drop.

Clean your test vial with ammonia before and after testing salt.

CYA drops 5-10 a month in the summer. If your water temperature is above 90, you might see drops up to 15.

Can you post a close up?

Before you do anything, get a full accurate panel and post the results.

Thx for this. I refreshed my testing knowledge and ran through everything again. The results are below but the only material change was to the salt (and I wanted to test it a second time but ran out of R-0718 so I'll leave that alone until the new vial comes next week).

I'm attaching 5 pictures:
- First is an attempt to capture the specs that gather below the return. They are small (<1/8 inch) and just squish/disintegrate when you touch them.
- Second, the build up on the plates in my SWG (unfortunately my camera didn't focus on them well but you get the idea). Note the bluish tint. I used to think this was from the GLB superblue but I haven't added that in a couple months. So I suppose some is still in suspension but my theory is that it's more related to the damaged plaster which is tinting the water (see below).
- Third, close up of the discolored plaster on my sundeck
- Fourth, more sundeck discoloration (some around the bubbler and more easily seen, some along the wall on the right)
- Fifth, another area of plaster discoloration on the sundeck

MY THEORY: My water chemistry make up is causing deterioration of the plaster. The plaster was a greyish color (as in the sundeck photos) but as the deterioration is occurring, it is causing a bluish-green tint to the water and also a bluish tint to the scaling on the SWG plates. The chemistry issue is related to excessive use of algaecide (high copper) and cal-hypo (driving up CH) over the previous two summers. I can thank my local pool store for those screw-ups! Or maybe the deterioration from my plaster is from high copper and as it deteriorates that drives up my CH?? In any even, my assumed action is drain about 40% of the water and effectively start over? Note that I had zero issues the first year (summer of 2022) and hadn't used any algaecide that year.
DISCLAIMER: This is all purely a guess! I have no training, experience or background on any of this. I'd love for someone to say "your issues are commonly caused by [x] and this is how [x] is typically dealt with".

FC- 4.5 (no change)
CC- 0 (no change)
Ph- 7.6 (no change; barring advice otherwise, I'm going to add about 3 oz of 31.45%/20' Baume acid to get to 7.5)
TA- 80 (decrease of 10, perhaps just a margin of error; note that I had to get my hot tub down to 70 last winter to get the scaling on the SWG to stop; PS- my reading of 86 in the original email was a typo- should have been 80)
CH- 625 (effectively no change; I used the 10ml method and hence the divisible by 25 vs 20 result)
CYA- 50 (increase of 10, perhaps just a margin of error)
Salt- 4000 (big increase so I'll be testing again when my 0718 comes; note that my SWG meter (for what that's worth) went from 3,650 yesterday to 3,750 today)
Temp- 82
CSI- +0.07 (decreased from +0.20)