[nelson4u]

I posted on this subject yesterday, but would like to get more input on water pumps. I am looking for a very quiet pump to run a 120 gallon FO tank in a home theater room.
It seems that all the very silent pumps are centrifugal and will heat up your tank water. I live in Phoenix and in the summer my house is right at 80 degrees so I can't have a pump that is going to heat tank a lot. I need advice from anyone that can tell me which magnetic drive pump is quietest, or if there is a silent pump out there that will not heat up tank ? I need to pump about 800 GPH @ 5' head.
I like the dolphin Ampmaster 2700 and 3000, but it has 1 1/2" in and out. Would I be able to use a Nu Clear canister filter, and UV sterilizer in line with 3/4 fittings or could I plumb 1" up to the filter and UV and go down to 3/4" at input and output of filter and UV and still have good results ? Also wondering about noise level of Blue line 40 HD compared to Little Giant or Gen X ? Can anyone give advice on pumps like Rainbow Lifeguard Quiet One, Velocity Silent from Custom Sea Life, Iwaki, Blueline, Gen X. I need to know how they perform ,and I also need it quiet as possible. Thank you for your time, MIKE

[dattack]

You are going to realize that most of the fan cool pumps are going to be a bit noisy.
I have tried Little Giant, Mak4, Iwakis. Very good pumps except eventually it will become noisy if not noisy to begin with. I can tolerate the slight noise but other people won't except near your entertainment system.

Velocity pumps are virtually silent but adds heat. Probably the quietest pump out there.

I wouldn't try the rainbow lifeguard quiet ones. They were noisier than the Mak4 I had.

I guess the only other quiet pump I have encounter were the ampmaster but as you stated the 1.5" plumbing might not fit your need. However, you can divert the excess flow from the ampmaster to your UV or possibly a chiller if you set up one.

[scubadude]

Sequence pumps are nice pumps and they are quiet too...little bit more pricey though

[Poseidon]

FWIW I use MAG pumps internal and have not noticed ANY change in water temp. I have TWO MAG 12's in my sump, one at each end and the tank temp stays constant. I know that they supposedly add heat, but I think when taking the VOLUME of water to heat, it is irrelevant. I guess what I'm saying is the PUMP would have to get VERY HOT to heat up 120 gallons of water. And they are as close to silent as any I've heard.