Most of the big GPH pumps have fans on them, thats where most people complain about noise. I have a small panworld without a fan, and I wouldnt know it was ruuning if I didnt put my hand on it, but have seen some bigger GPH panworlds that had a nice hum due to the fan on them. Just my two cents. Try finding a pump that boasts its quiet running fan maybe?!?!?