sounds like it will work but why not just add more baffles instead of drilling all those holes ?? here is my sump and it took me all of 20 minutes to build. the flow rate is high but the current is low enough to let some frags do a little extra growing before they get to the main tank ...
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sorry it took so long ... had to take new pics
sorry the last pic is so blurry looking, it is coralline growning on the glass.