thats a good idea eric... I was concidering some sort of meter attachment I could add to the PVC but logistically thats just not going to happen even if I did have the meter.

I think I'll just measure the rate at which it fills up on my next water change. All I need to do is keep the return section of the sump filled (buckets will do the trick) and let her rip. The math after that should elementary.

thats good thinking eric, thanks

P.S. does 6750gph sound right???