CYA and tri-chlor

[adesalvo]

You didn't say the size of your pool so you'll probably need to scale this number down accordingly for a larger pool.

Sorry, 25,000 gallon IG vinyl

If you have a DE or sand filter that you clean/backwash regularly then this will dilute the pool water so you won't have as much buildup. Same for rain that overflows the pool or for splash-out.

I have a unique filter/pump system that uses cloth filter bags. The pool manufacturer is from Europe and is sold in the US as Utopia Pools.

If you let the CYA get higher, you'll have to raise the FC level (see Ben's Best Guess CYA chart) or you'll have to drain/refill periodically to keep the CYA lower or you'll have to use an algaecide (PolyQuat 60) to prevent algae (the latter option being more expensive).

I have been using various algaecides over the years. I am not sure if i should continue this practice. I am leaning towards doing so.

You say you start with 0 ppm CYA after the winter. Do you let your chlorine go to 0 ppm FC over the winter or do you maintain the FC level? If you don't add chlorine, do you find that you have to use a lot of chlorine to clear your pool on opening? Does it have algae upon opening?

My chlorine does go to zero over the winter. I have added 8 gallons of bleach in two days. My Taylor kit is in the mail (Ben's kit never came) and I ran out of DPT tabs at the end of last year. So no real numbers...just pH which has been good.

My pool was opened yesterday and is starting to clear. Mostly dirt...maybe some algea.

Thanks Richard and Janet, this was exactly the info I was looking to get

Tony