I made my own protein skimmer a while ago for my 125g FOWLR
. The tank has 5 fish in it: blue tang, clown fish, six line wrasse, scooter blenny and green chromis.
I have an airline at the intake of the pump which creates fine air bubbles. The bubbles make it all the way through the chamber like they are supposed to but I never get much protein foam. I've never had the foam head make it into the collection cup in the few years that its been running. Is this due to a design flaw in the skimmer or because my bio load is small?