What's the Difference between a Flow-Biased Pump and Pressure Rated Pump?

sgrosenb · 10/15/2008, 08:16 PM

I'm sure it's quite simple, but I don't know the answer... Thanks for the help.

jdieck · 10/15/2008, 08:23 PM

Their impellers, volute and rotational speeds are designed differently, one to create more discharge pressure at the sacrifice of amount of flow and the other the oposite, it is more geared toward producing more flow at the sacrifice of discharge preassure.

Higher discharge pressure will be required for certain applications, like pumping to a higher level (like a return from a basement sump to the first floor tank). High flow is more useful for applications that do not imply fighting much back pressure like in a recirculatin or closed loop pump.

sgrosenb · 10/15/2008, 08:41 PM

Thank for the help Jdieck. So if I purchased a Reeflo Dart for as my return pump for my 156g tank (sump is 75 gallons), which will be pumping up a tube about 5 feet high, I should be good?

WaterKeeper · 10/15/2008, 08:58 PM

For just a five foot lift a flow biased is great. Not a lot of back pressure on a short lift, so flow is more important than dischange head.

jdieck · 10/15/2008, 09:02 PM

Quote:

Originally posted by sgrosenb
Thank for the help Jdieck. So if I purchased a Reeflo Dart for as my return pump for my 156g tank (sump is 75 gallons), which will be pumping up a tube about 5 feet high, I should be good?

Depends on the flow you are looking for as the head pressure increases (flow decreases) not only with the height but also with the diameter of the return pipe or hose, the number and type of fittings, etc.
You can use the flow calculator to determine the actual flow you can get from the pump. If your pump is not listed try selecting a pump with similar performance curve.
http://reefcentral.com/calc/hlc2.php

10/15/2008, 08:16 PM	#1
sgrosenb Premium Member Join Date: Sep 2008 Posts: 160	What's the Difference between a Flow-Biased Pump and Pressure Rated Pump? I'm sure it's quite simple, but I don't know the answer... Thanks for the help.

10/15/2008, 08:23 PM	#2
jdieck Registered Member Join Date: Dec 2002 Location: Maumee, OH Posts: 15,673	Their impellers, volute and rotational speeds are designed differently, one to create more discharge pressure at the sacrifice of amount of flow and the other the oposite, it is more geared toward producing more flow at the sacrifice of discharge preassure. Higher discharge pressure will be required for certain applications, like pumping to a higher level (like a return from a basement sump to the first floor tank). High flow is more useful for applications that do not imply fighting much back pressure like in a recirculatin or closed loop pump. __________________ Did I write what I wrote? What the heck am I talking about! Well..... Nevermind. Current Tank Info: 225 gal reef, DSB, 40 g sump w/ LRT100 return, 37 g pre-sump, 3 MH 250 W 15K, 4 96 W PC dual actinic,ETS 1500 Skim.w/LRT70, 20 lb Ca R., 40 W UV, 1/3 HP chiller, two 350 W Htrs, Neptune II Cont., 330 P LR/ 330 P LS. 55 gal Refugium

10/15/2008, 08:58 PM	#4
WaterKeeper Bogus Information Expert Join Date: Oct 2000 Location: SW Ohio Posts: 16,147	For just a five foot lift a flow biased is great. Not a lot of back pressure on a short lift, so flow is more important than dischange head. __________________ "Leading the information hungry reefer down the road to starvation" Tom Current Tank Info: 130 Now out of service and a 29

10/15/2008, 08:41 PM	#3
sgrosenb Premium Member Join Date: Sep 2008 Posts: 160	Thank for the help Jdieck. So if I purchased a Reeflo Dart for as my return pump for my 156g tank (sump is 75 gallons), which will be pumping up a tube about 5 feet high, I should be good?