I got a Biocube 29g since ehm...3 years or so. what i did is remove the bio balls they only cause all kinds of stuff to get tangled up there and rise your ammonia and so on. and then i put live rock piece (tiny ones) in the back and put some chaeto allergy in the back....i pulled out the carbon thing and replaced it with filter floss. put the protein skimmer in the first chamber ...and thats pretty much it. got a tiny light on the back sitting. really nothing fancy. i cut my lid and put a wave point light fixture on top of it. those run with T5s. Didn't have the money for LEDs at the time. works for my stuff so far. never had any problems. Sometimes i put a small bag of carbon in the last chamber just for a week or so.
-.- im kinda late nvm