You want to skim water straight from the tank, and you want you fuge to have water straight from the tank. Have 2 drains on each end of the sump, and have your return in the middle. If you want to be safe, get drains that double the flow of your return pump, use valves to tune them down, so if one drain gets clogged you can still run the other one on full until you fix the other drain.
30L w/10gallon sump 4xt5ho; Up and running:125g long, 30g sump, 50g fuge.
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