You said your PH is 8.0 last time you checked. What time of day was that?
If the high of day is 8.0 then it could be dipping below 7.7 when lights are off.
Constant drop or low in magnesium can cause depressed PH levels
If the high of day is 8.0 then it could be dipping below 7.7 when lights are off.
Constant drop or low in magnesium can cause depressed PH levels