lol I guess its subjective. I recently put all my air pumps on top of the tanks and removed the check valves for more air flow and I am realizing they are kind of noisy nothing intolerable but I only have a 29 gallon in my bedroom so meh no biggie on the noise factor some people are more sensitive.sonycrr;3164388; said:i have a rena 300 and 100 and these things are loud.