Bought a neptune full system second hand off a fellow. My PH has read around like 7.6-7.7 consistently, but I dont know if the probe is good as you should replace after 2 years and I am not sure how long he has the probe for. So I have just used it to watch trends. But recently (Last month) my PH is peaking at 7.99 and 7.75 at night. Is there a explanation to the rise of PH with no changes in the system? No CO2 Scrubber, No fuge, Same skimmer as always, No new changes coral or fish, No new dosing besides correcting magnesium to 1450 from 1100.
