I am currently running a mag7 on a closed loop. It's a hang on type with the pump mounted on the back of the stand.

I'm not real happy with the noise from the mag7 pump. Ideas on a super quiet pump for a CL?

I run a Quiet one inside my sump and it seems to be very quiet. I bought mine over a year ago and it has never gave me any problems.

I'm a big fan of sequence pumps (made by Reeflo). Extremely efficient and you can adjust water flow by tuning the motor, not restricting output with a valve. Pricing on them is good too.

We're using a PanWorld external pump for our closed loop and a QuietOne submersible for the sump return. Both are exceptionally quiet compared to the Mag pumps I've heard. Also, neither of these pumps produce any appreciable heat that gets dissipated into the water return stream. We've been VERY happy with their performance over the last year and have similar pumps (same brands...smaller capacity) that we're getting ready to install in our soon to be running 55.

Iwaki- with japanise motors :D