Can pumps be lower than sump & PS???

[rjs5134]

I've posted numerous times about the need for an extremely quiet pump that would not create a noise issue in my living room. I've concluded that the Velocity pumps may be the quietest, but may create heat which is an issue. Since I can't have my cake and eat it too, I come to the following question:

Does anyone see a problem with using an external pump to operate the MRC MR-2 skimmer if the skimmer is next to the sump, but the pump is on a shelf in the cellar, just below where the tank sits? In addition, would it be a problem for another external pump to be on the same shelf, approximately 3' below the floor where the tank is, to draw from the sump through a chiller and all the way back up to the tank return? Obviously the additional head will have to be taken into account.

I just don't see how I can operate such large pumps, significantly larger than what operate now, without increasing the heat and limiting noise, or increasing noise and limiting heat. I'm dying to get this worked out as I now have my new skimmer and want to get it working desperately.

Thanks

Rob

[reefracer]

I think you can do both senarios you mention, after all that's what head capaicty of pumps is all about. I can't recommend which pump but their head capacities are published at least that ones that are capable anyway. I do know about the T4's, yes very, very quiet and worth about 5 degrees each.

[Frogfish]

If you look at the pump curves, the head is considered Total Differential Head, or TDH. The key here being differential. If your pump is located below the water source by 3' (from the top of the liquid) then you can subtract that from your discharge head calculation.

For example. If your pump is 3' below the water level and your are returning the pump discharge back to the same water level your total head is 0 (plus any friction loss in the piping which I am ignoring for this example)

In the same example if your pump is 3' below your sump and you are pumping up to the display which is 6' above the pump then the differential head is 3'. Again I am ignoring piping friction loss.

So yes, either scenario will work. You will have to take into account the piping friction loss, but there are web sites to do so if you plug in your pipe length and elbows etc.

And just so that you know, I sell industrial pump for a living so I know what I am talking about. If only I had a 10.000 gallon aquarium I could supply myself with an awesome pump!!!

[rjs5134]

Thanks Frogfish and Reefracer. Thats exactly what I was looking for. Problem solved.