I'm using the aquaticlife skimmer on my 29g biocube. It can pull alot of gunk but it is a pain to dial in. But other than that I would buy another. lol In fact, this is my second one as the first one I got was used and only lasted me 2 years.
Theres not many small skimmer options for small tanks unfortunately. Other options that are more money include the hydor slim skim or a tunze9002 (i think thats the smaller one).
180g Reef - 60g Rimless Reef -90G FOWLR- 125g Malawi Cichlids- 40b REEF- 34g Fresh Planted-working on- 20L FOWLR- working on
I have a mix of many different saltwater fish amongst my tanks, but I love my Tangs most of all.