I'm filling a large community pool after a draining for various maintenance. it's going to take another day or two fill completely, so my queston isd, when should I begin hitting the pool with BBB? Ph is pretty good already (7 to 7.2), though our present testing resources are old. Calcium is WAY low, alkalinity a bit low.
Should I start guessing now, as it fills, or wait a bit until the pool is full?
Thanks for your help!