overflow water level keeps changing

[reef tank 2.0]

is it common for the overflow water level to change? I haven't touched the gate vales in awhile. the water level keeps fluctuating on it's own. what is causing this?

 

[Idech]

I’m new at sumps and kind of have the same problem. I was told to increase the pump speed, as it wasn’t enough to sustain stability. It worked.

It might be another cause in your case, but worth trying.