I can hear the skilter from the next room and can be annoying if you like it quiet at night.
I've had mine for about 7 months in my 10-gal
reef, but I have to get rid of it because of the millions of micro bubbles - they are very detrimental to my seahorse (actually, so is the small tank
). I also agree 100% with emorrisson33 that it is very loud and a protein skimmer is a better way to go.
If you have a small tank, a bio-wheel filter might be worth looking into, otherwise, I'd go with emorrisson33's advice.