More predictable Skimmer???

[ickmagnet]

I have my Beckett skimmer in my sump (just resting above water line actually) and have the pump (mag 18) submerged. I don't have an ATO system (not enough room for it) and change the water manually everye 4-6 days to bring it back to the right water level. The problem is, any time there is a change to the water level in the sump, the skimmer goes crazy and will fill up the waste collector at an alarming rate ( this has resulted in waste overflow on a few ocassions). Other times, i will have to adjust the gate valve to increase the skimmate level. In any event, there is always some adjustment required.

Is there a skimmer out there that doesn't have these types of problems i.e, will produce at a constant rate despite water level?