Water Pumps

PBearslax36 · 06-17-2005, 09:05 AM

I am looking into getting a Mag Drive Water Pump that is rated for a flow of 500gph. They have a chart stating that at:

2': 425gph
5': 250 gph
10': shut off

My question is, does this info mean the flow of water going horizontal along the ground, or vertical traveling up from the bottom of the tank to the top?

lizardarm · 06-17-2005, 09:33 AM

they are talking about head pressure. this means going up (vertical).
the diamater of the piping and any turns in the pipe, also have to be factored into the head pressure.
it's a good idea to assume that you will be working against at least 3'-4' of head pressure when trying to determine what pump to buy.
a mag7 might be a better bet if you are shooting for 500gph.

lizardarm · 06-17-2005, 09:36 AM

what are you planning to use the pump for?

PBearslax36 · 06-17-2005, 10:33 AM

Quote:

Originally Posted by lizardarm

they are talking about head pressure. this means going up (vertical).
the diamater of the piping and any turns in the pipe, also have to be factored into the head pressure. so the smaller the diameter of tubing would mean more or less flow?
it's a good idea to assume that you will be working against at least 3'-4' of head pressure when trying to determine what pump to buy.
a mag7 might be a better bet if you are shooting for 500gph.

PBearslax36 · 06-17-2005, 10:34 AM

Quote:

Originally Posted by lizardarm

what are you planning to use the pump for?

a return to the main tank form my refugium

lizardarm · 06-17-2005, 10:46 AM

use 3/4" thin wall pvc. you can get away with 1/2" on smaller pumps, but if you're going to run a mag5 or higher, it would be best to use the 3/4". it will create less back pressure, thus maximizing the pumps output.
if you are trying to pump through a smaller line, it will reduce the flow because the pump has to work harder. what comes out the other end, will come out at a higher velocity, but it's not going to be actually more water passing by.

lizardarm · 06-17-2005, 10:50 AM

going from the fuge up to the tank (assuming that the fuge is under the stand) is going to be four+ feet up. plus there will be bends in the pipe. i think i remember seeing somewhere that each 90 degree turn (or maybe it was every two turns) equals another foot of head pressure. so try to use 45's when you can.