One Cubic Meter of Ocean

[sphelps]

Originally Posted by Scythanith

So you put the returns on opposite sides of the sump mostly due to space constraints on the left side of the upper sump correct?

I wonder if I should ask Denny to change my design to have the two returns on the sump side by side? The stacked design may give me similar issues. If we lower the sump then we take away the silent aspect of the overflow box to sump don't we?

Yeah space constraints mainly, couldn't fit two on one side that's for sure. Not sure if the frag tank will benefit more from opposing flow or single direction, ultimately it probably doesn't matter. I wouldn't change yours as that means you'll probably have to plumb underneath which I only did cause I had to.

Noise won't be an issue, you'll need standpipes in the overflow to maintain the water level in the overflow box but the drop will still be small enough to essentially maintain the lines full of water or at full siphon meaning no air and no noise. With your two inch pipes I'd aim for a 6" height difference between overflow water level and the frag tank water level. Worst case you stick a gate valve on one of the lines and go herbie but I don't see that being necessary. I'll get a plan drawn up for you next week