No CYA

[wilcfr]

Okay here is what's going on. We had our pool drained, cleaned and refilled this spring. We had the filter dumped and new sand put in and a new pump and skimmer installed. We forgot to put CYA in after we refilled it so when we opened it a week after our Memorial Day party we were greeted by a smelly, green swamp. We shocked the pool, put in some algicide and got it back to blue, but cloudy. Since then we have been trying to get some CYA to show in the pool to stabilize the SWG chlorine. We have added 24 lbs to a 32K pool over the course of 2.5 weeks and have nothing to show for it. We have tested it with our old Hach kit and our new Taylor DPD kit. Our standard procedure is to put 4 lbs through the skimmer and then wait for 4-6 hours and add the next 4. I backwashed prior to adding the CYA and again about 3 days after. I wait for at least 3 days to check the levels. We have done this 3 times and have zero CYA indicated. Our other numbers are good with the exception of our alkalinity.

Specs.

32K gunnite, SWG pool
salt concentration 3.3
pH 7.7
alkalinity 270 ( put 1 gallon MA in tonight to try and lower the Alk, we will deal with pH later)
Calcium 270 (standard for the areas city water)

The pool temp has been very high the last few week running about 95-96 degrees
When we check the inlet water for chlorine it shows 6-10 ppm per the Taylor kit so the generator is working great, but it was also running at 100% until today when I turned it down to 70%. But we won't be able to keep the pool clear unless we can get some CYA into the pool.

Any help would be greatly appreciated. We have never had this problem before. We are stumped.

[AnnaK]

It's possible that the CYA is being backwashed out of the filter before it has fully dissolved. We normally recommend that you start with a clean filter, then add CYA via the skimmer and wait a good week before backwashing, if that's necessary. Or add CYA using the sock-in-front-of-a-return method which doesn't get affected by backwashing.

Until you can get a testable CYA level your SWCG is working too hard. I'd turn it off and go with straight bleach or dichlor powder for a while.

[Watermom]

I agree with Anna that you should turn off the SWCG for now. 24 lbs. of stabilizer in your pool would add 95ppm of CYA. Since you don't know how much may have been backwashed out, I wouldn't use any stabilized forms of chlorine until you can verify the reading, so I would use bleach and not dichlor.

Welcome to the Pool Forum, by the way!

[wilcfr]

Okay so I tried my version of the CYA in the sock trick and it seems to have helped. The CYA level is now at 30 which is an improvement. The Alkalinity on the other hand is still a mystery. We put 1 gal of Muriatic Acid in the pool yesterday. Today we checked the pool and found the pH down 4 points to 7.3 and the Alkalinity went up from 270 to over 300. We are going try aeration to see if that helps.

[Watermom]

I can't see how that is possible for the alk to go up. Go ahead and add a little more acid and then aerate the pH back up and repeat the cycle until your Alk is where you want it.