Sump Design Question

[ksalt]

Where the skimmer is concerned, it placed into a compartment with a consistent water level. Most skimmers have a manufacturer suggested depth. That said, evaporation comes from the other (return section) compartment that the skimmer (drain) feeds. Then you can add refugiums, etc., etc..

[ZachAttack]

For the skimmer, as long as you have a baffle for separating the micro bubbles between the skimmer and the return section, you don't need anything else