Re What Is Considered High Ph ?

Hi Ally2,

If your PH were below 5 or above 9, that would be alarming and would most likely need addressed. If it's somewhere in between, then it's most likely fine but many fish fare better at different ranges of the spectrum. What is much more important, though, is that the fish you have are suited to the water hardness - PH, while important, is of secondary importance to that.