Organic stains on liner

[joelg2k]

PoolDoc,

thanks for the info - my current CYA level is between 30 and 35 ppm. How high can I shock the pool without taking the risk to damage the liner ?

Thanks again

Joelg2k

[PoolDoc]

There's no safe answer to that -- some liners are not color fast, period. We've researched this extensively, and have not found ANY way to distinguish the color-fast ones from the non-color-fast ones, except to note that, if yours bleaches out at moderate chlorine levels . . . then it's one of the not-fast ones.

That said, you *should* be able to hold the 'shock' levels in the Best Guess chart (see link in my signature) without problems. No guarantees, however.