There have been many instances of CYA disappearing over the winter and leaving ammonia in your pool.....ammonia is a chlorine hog.reidsmith said:Dave,
I do close the pool in winter.
The CYA was low this year. The first time in years. I added 4 lbs. CYA and it came up to just above 40. It's gone up a little with the tri-chlor tabs since then.
You mentioned 15 gal. of bleach. I have 12.5% chlorine so do you think 8 gal. should be enough?
Reid
The answer is still more chlorine, it'll just take a LOT more than you would expect. If you posted how big your pool is, I can't see it so I'm not sure how much chlorine you need but 8 gallons of 12% seems like you might come up a little short.
You will never waste it and it's good not to run out once you start the process so I'd get a bunch more.....maybe double that......again, you won't waste it.
Chlorine, chlorine, and more chlorine will get rid of whatever organics are in your pool and allow you to start holding normal FC levels.
Use Jason's calc in my sig to help you figure your dosages.