Hi Chaotic,
I have a small 15 gal fuge from modified
wet dry filter that came w/125 gal tank. Fuge is outside of my sump used for tank on small 2 foot stand I made from home despot wood scraps(FREEBEES!!).
300 gph pump from sump with gravity drain to tank from 1 1/2'' pipe plumbed up into fuge tank to prevent overflow. Used baffles in fuge to place acryllic plates to separate fuge mud from return space and added small clear pro 75 skimmer($70.) in return space to filter water before return to sump. Lighting is simlple 100w Grow Bulb on timer since room gets overhead sunlight from skylights.
Currently have cheato algae,
nassarius snails and will be adding copepods from ''tigger pods'' solution.
HTH
Doug