Water level too high

[IJC]

I do have teeth, and they're probably about an inch and a half deep. The top of the box (top of the teeth) is flush with the top of the tank's trim. I can see that the teeth have already been lengthened a bit and they are not all the exact same length - meaning that the difference between my "while running" tank level and my "power off" tank level is bigger than it need be. Obviously, the water level drops to the height of the lowest tooth. So I want to be carefull not to increase the amount of water that could end up in my sump, or maybe even decrease it. (I'm all about the peace of mind)
I was considering cutting the teeth right off, and just puting an inch or two of egg crate (or something fence-like) around the top.
Thanks for the help guys.