Lowering my tank water level

[olingerjccj]

I have been messing around with this for a while, I want to lower my tank water level down about a inch or 2. Every time I pull some water out it just adds more from the sump. I have tried to move my collection cup down a bit but it really does not help. Here are some pictures any help would be appericated.
on the left of my sump pulls water in middle is for bubbles and the right is my return filter bag.

 

[schnutzzy]

It's hard to tell from pic, but if you have a overflow box there is a plastic wing nut that lets you adjust it up or down. If you move it down the water level will go down. If that doesn't work you can put a ball valve on your return line and adjust the flow so that the return line isn't faster than your overflow box can handle. I hope that helps, because I had the same problem and the ball valve solved it.

 

[namas05]

Yep ball valve on the return line will do the trick.
Lowering the overflow will not slow down the return. It will only pull water from lower in the tank not lower the amount in the tank.
Unless you shut off your return pump, rull out the desired water level, lower the overflow box, and then equalize the overflow and the return. but more than likely you will have to still have a control on the return to help with that.

 

[prime311]

Well assuming the overflow output is higher then the return output(as it should be) then lowering the overflow should lower the water level in the tank. Adjusting the ball valve to lower your return output is only getting your tank to where it should've been in the first place.