So yesterday I was looking behind one of my tanks and discovered water everywhere. "Fortunately" it was just my aquaclear 110 leaking. The outflow cracked underneath and I have no idea how long it had been going on for. There was water buildup all along the towel I kept under the tank and the stand soaked some up too. Mold was beginning to grow on the wall behind it as well. The mold was just surface so I was able to kill the spores with vinegar and my local Petsmart exchanged me for a new filter. I am not trying to sway people from buying these filters (I currently run 5 and will run more in the future) but just a word of caution, be careful with the plastic. This seems a common place for them to break. Also if you didn't before I suggest doing a tank inspection every week when you change water, it is what I will be doing in the future to catch problems like these in the early stages.