pH range question for those who have a controller

[abcha0s]

Originally Posted by The Grizz

So I finally have my pH probe calibrated on my Profilux 2ex controller. Right ATM it reads 8.14, I have noticed that it jumps from 8 - 8.3ish from morning to late afternoon and then drops down closer to 8ish by late evening.

Is this a normal occurrence?

During the day, the plant life in your tank will consume co2. This lowers the co2 in your tank and the pH will rise. At night, the reverse is true and your pH will drop. This is why many people run their refugiums on a reverse light cycle. The idea is to balance out the production and consumption of co2.

- Brad