What is the most quiet return pumps?

[mr_alberta]

I got this message from Roger Vitko over at Reef Central regarding the Master Electronic Pump, maybe it'll be helpful to you:

the 1073.090 can be used submerse or external. It is a large pump and makes some noise and the noise is worse with submerse use because it vibrates against the glass of the sump. External it makes about the same amount of noise as a large Iwaki or Dart pump.