We recently had a new pool and spa heater installed - after 6 weeks most of the copper has been corroded in the heat exchanger and now needs to be replaced. The sevice tech stated the Ph had been too low/too much muratic acid and caused the issue. Weekly we have someone come and "mantain" the chemicals for the pool. They stated that they think some recent grout work caused the low PH and not their chemical service. Can any type of grout lower the PH or is that a stretch?

From the last water test a week before the leak:
FAC: 5
TAC: 5
CYA: 99
TA: 3
PH: 7
Copper: 3+...
Iron: 0
TDS: 2500
Pho: 0

Approx 10,00 gal

Thanks from a new member!