internal sump return pump vs external?

[Milad]

Are the internal sump pumps quieter than the external pumps like the dart?

[bvlester]

I don't know I have not changed my sump over yet but I am. I think the internal sump pumps are easer to clean and maintain. My internal sump pumps are quiet I don't notice them running at all.

Bill

[plutoniumJoe]

Pumps like the Dart are extremely quite as long as they are installed correctly, just a nice gentle hum. I also have a PanWorld100PXX, it handles 1/3 the water and is 3 times as loud.

[Madreefer]

They may be quieter but also adding heat to the water.

[banditpowdercoat]

Took me a while, but now that I run external, I never want an internal again. Much less heat.

[kien]

One of the reasons why internal pumps are generally quieter is because the water dampens a lot of noise. That is unless your return pump is rubbing up against something like the tank wall or a pipe or something. A lot of internal pumps will come with cushions/foam to cover the bottom so that it isn't vibrating against the bottom of the tank glass. Same principle applies to external pumps in that the key is to reduce vibration as much as possible. Although external pumps don't have the luxury of water to aid in noise dampening, they do have the luxury of being able to be bolted securely to something.

Heat is another issue in itself, but that wasn't your question :-)

[Aqua Man]

I have two set ups one of each. I have taken notice of them after reading all of your posts.

My in wall tank is a 100 gallon custom with a 65 gallon 3 stage sump. I run 2 3/4" returns with line loc which is powered by 2 seperate MagDrive1000's pumps. Generally quiet and virtually indestructable these pumps do put off mild hum.

My coral breeding tank is a 300+ gallon custom with a 100 gallon 6 stage sump with a natural plant refuge. I run 2x 1" returns with no line loc which is powered by a single massive external Dart 4700 gallon/hr pump. I cannot hear a sound from it! Absolutely no noise, I do have it screwed to a chunk of 2x8 which is PL4000'd to the cement floor. I did however level it in both direactions, this may be why. As for the heating up comment, I put my hand on it and it was ice cold. It has a section that throws cool air, but the impeller housing may heat up, not sure.