Skimmer overflowing

[DoctorR]

I have a SC-S250 skimmer that has started overflowing every 2 - 3 days. Not sure what's changed because I've been running for almost 2 years now without this issue. The air line seems to be clear. Skims great for several days and then I come home to find it pushing clear water out the top. ?Any suggestions would be appreciated. ??

 

[jenkinscrew]

Hmmm, when is the last time you did a full cleaning on it (pump and body)?

 

[Mike R]

Is your water level in the sump fluctuating for some strange reason? ?

 

[DoctorR]

I clean everything that is obvious. I wonder if I'm missing something.?

 

[DoctorR]

In fact, the water level has been dropping and then surging in the overflow box and then through the drain line. The box and line all look clear.?