First, let me introduce myself. I am Babe the Blue Ox from NE Oklahoma, and I am never going to the pool store again.
I have a 30 ft. above ground pool, 23,800 gallons. I've been using pool store chemicals for the past 3 years and always have had good luck until....
We took an 11 day vacation recently. Came home a week ago and found a slime green pool. Everything seemed ok test wise, but the algae was so thick that you couldn't see more than 6 inches down.
I had the pool guy test the water and we found that the CYA had risen off the charts. I've removed and refilled half the water twice to get it down to an alleged 35 CYA. I then talked to 3 guys at the store, and each of them gave me a different solution, all of which involved a bottle, tub or vat of expensive gunk. I thanked them kindly and left, vowing to not return.
I went straight to wal-mart and bought 6 big jugs of bleach, as I'm ready to become a BBB convert. However, the bleach does not seem to be working as the pool is still about the same shade of nasty.
I picked up a 6-way test kit today and found that the CYA is close to 60 and that the pool store calculation was way off.
I've been using the pool calculator to get my free chlorine level to 16, but now I find that it should really be 24.
Here are my readings (from my own testing):
I bought some more bleach and have added enough to raise chlorine to 24. I've brushed once per day according to the pool school guidelines. What's next?