Aeration/waterfall and ALK question

[waterbear]

If you keep your pH on the low side (7.2 to 7.4 ) then the constant airation over time has probably been lowering your Alk. I would raise it if it were my pool. It might help keep your pH a bit more stable and the ALK and CH work togehter to help protect the plaster. You might want to consider running your pH closer to 7.6 to help minimize the effects of the constant airation on the ALK.