There are plenty of available apps out there that determine decibel levels around the house. Download one or two and see just how noisy your system is. When you post up the numbers post what equipment your running as well. For myself, my tank averages around 50-55 decibels when I sit on the couch 8-10ft away from the tank with doors on the stand shut. Right beside the tank around 55-60. Inside the sump compartment 75 ish. Equipment that runs constantly: 3 wavemakers, 3 lighting systems with fans, protein skimmer and the sump/overflow. When all fans in the room are going, windows open I read around 71 DB on the couch as the ceiling fan is noisy.