well i know the ball valves can be a bit tricky to dial in because they kinda stick in places but with a bit of fiddling once they are set that should be it. Did you see the ball valve in the sump? Albert tells me it should allow me to control height in one side of the sump for the skimmer

should be fun to try
i cant wait to build my next tank, i have had so much fun building this one. now if only my friend Matt who this tank is for would get an account on canreef.....
Richard