Spike,
I'll add in a few bits here..
From experience I can back up what Tony has said about flow in the sump. Go for hte minimum or a decen't flow rate through the sump. Say about 700-900 GPH. Then add in some sort of closed loop.
I am setting up a new system and will only have a small return pump but have a MAK4 on a losed loop system. I am also looking into a SCWD on say a MAG9 or 3MD for that alone to create some more random flow patterns.
For my returns I went shopping down south and purchased Loc line tubing. It allows me to angle the flow in any direction/angle I chose.
Take a peek online for that stuff. It is excellent for this application.
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Darren
Always strive for the optimum environment, not the minimum environment
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