My SWG (IC40) appears to be done after 4 years (of 12 hrs per day during season). It never quite kept up with demand, so I'm trying to get the replacement to do a better job and longer by making some fundamental changes to the chemistry BEFORE the new one goes in (also decreasing pool run time without sacrificing solar benefits).
Using taylor drop tests to measure. Pool is about 28K. Plaster, SWG, solar, DE. Currently using liquid chlorine (8.25 bleach) to sanitize until water balances and new SWG goes in.
Here are my challenges...
My TA has been 110-120 since I filled the pool 4 years ago. I've been adding MA the last few days and aerating (per pool school article on lowering TA) to try and drive it down to the SWG target of 70. I have tubing stuck in the eyeballs, and return water is creating a nice blanket of little bubbles from both returns, and from the spa spillover. I can easily add MA to lower pH into the low 7's, but TA continues to test at 110. Aeration is allowing pH to rise (slowly), but shouldn't I also be seeing the TA numbers decrease as I dump in acid? I've taken pH down to 7.0-7.2 twice now in the last two days (about 1.5 gallons of MA), and TA still tests at 110.
I had a challenge last year with attaining and sustaining CYA in the 70-ish range. 30-40 seems to be a wall. I kept adding CYA, and it wasn't increasing. The season ended before I sorted it all out. I opened the pool to a CYA of about 20 this year. I've added about 12 lbs to date (which should be about the right amount). I am giving it a few more days to see the effects. Anything else I should be checking? I have not been adding water to the pool, and we have not had enough rain to cause overflow. I have no drains or leaks or automated fillers. I may not have a problem this year - but it feels like I do. It feels like something is consuming CYA...
Other relevant stats:
- water temp: 86
- FC: 7, CC: 0
- CH: 300