Quietest return pump 250-500gph?

[Cubeman]

I am looking for peoples suggestions on the quietest submersible small pump in the 250-500gph range. Head height is not a factor in this case. Is there any such thing as a silent pump or will I always have to put up with the hum and rattle with a pump of this size? Thanks in advance for your input...

[Nano]

IMO...

Tunze silence pumps are exactly that. Silent. I also hear the DC pumps are quite quiet too.

A pump that small should be quiet either way as theres not a lot going on in those little ones