The Oceanic BioCube Skimmer is crap if it's not taken care of. I also have one on my 14G. The air stone needs to be changed every 3 weeks more or less, keep an eye on it. The chamber should be cleaned every few days. Stay on top of weekly water changes and you
should be fine. I would not just run the tank with no protein skimmer though. I suggest changing the airline tubing as well. This seemed to help ours a lot. If you ever stop running the skimmer and try to start it back up, you'll have issues, that's when mine crapped out.
Good luck.