Looking for a sump for a 75g tank. Thinking maybe a 20g long or so. Pretty new to all this equipment so not sure what I need to do to build one. My tank has been set up since Nov of last year and I'm using a wet/dry at the moment. Anyone have any advice on how to make a sump with a refugium?? I'll also have my protein skimmer in there along with my return pump obviously. thanks in advance!!!