This little skimmer works surprisingly well for its size. It started pulling skimmate out of the tank within a couple of days. The common complaints about the suction cups are true (they don't hold well), which makes it difficult to keep it adjusted properly. That said my tank is noticeably cleaner after two weeks.

If you have some time and creativity you can get this to work inside your CORALIFE BIOCUBE 29 I have to admit I was ready to smash this thing on the floor because the suction cups suck and the unit ends up falling to the bottom of your first chamber and then you get a gazillions micro bubbles and no results, I did do the upgrade to the air line right away which helps out I used air tubing all the way to the impeller housing and used about 1 foot and a half extra you still hear gargling but not that much. Aside from that I managed to find some info on a forum called reefcentral.com and used a few pointers from them to get this thing to stay up to the right water level along with some zip ties and a few extra plastic pieces I had laying around I got this skimmer to stay at the right night and it is skimming nicely broke right in and got some tea colored skim mate a day later and it's getting dryer and darker now. I had to knock off one star because it had put me to work and even do some mods that everyone and their mothers always complains about (air intake noise) that aquatic life just seems to ignore, but I would rather use this over a lime wood skimmer any day and until CORALIFE not oceanic makes a better price conscience skimmer that actually fits the biocube the right way with no struggle I will use this product because its a needle wheel impeller and does a better job than lime wood IMO

Mine took about a month or so to break in. Once that was over it's worked quite well on my 29gal bio cube. I also learned to not clean the riser section of the collection cup. I think the slime coat it develops assists with the bubble migration. I rinse it still but I don't scrub it clean. I get decent skim from it though it's always been a little wet.