I've neglected my pool but have also lost faith in local pool stores and services. My 16k fiberglass pool was great two months ago, then we had a heat wave that seemed to prompt an algae bloom. Told to add ten or more gallons chlorine did not curb the algae. Adding cyanuric as recommended did nothing. Ph appears a little high. Acid demand says add 3 qt. muriatic. Most other tests register very low PPM. I"m spooked. In such a situation, which characteristic do I try to cure first? Ph, Calcium Hardness, total chlorine? Thanks for any help.