Return pump question

[Gimplar]

Anyone know what GPH for a return pump running at 29 gal, with SQWD and 1/2" hosing, its going up a heigh or around 3 1/2'

[luminary]

I'm not sure what you're asking....do you want to know what your tank flow should be? or do you have a particular pump in mind and want to know what the SQWD, 1/2" ahd 3.5' head will do to the overall flow rate?

[ReefArtist]

I'm not sure what your asking either but here's some information about the output of the SCWD. If you look at the "Head Loss Calculator" and if you put these calculations together - you'll be very close.

Flow into SCWD SCWD TD Output Efficiency Switching Duration
150 gph 90 gph 60% 22 seconds
180 gph 120 gph 65% 16 seconds
240 gph 180 gph 75% 12 seconds
270 gph 210 gph 80% 10 seconds
330 gph 240 gph 80% 9 seconds
400 gph 360 gph 90% 7 seconds
600 gph 540 gph 90% 5 seconds
720 gph 660 gph 90% 4 seconds

[alizarin]

To answer your question you need to address all of these:

1) You need to decide on what kind of flow you want. As far as how much flow SHOULD you have for a 29g I think the rule of thumb is 10-20x the tank volume so about 300 to 600 gph for your tank. What kind of corals are you keeping? I think SPS like it higher flow, some softies like it a little softer.

2) You need to know what the max flow rate of your overflow is so you don't overwealm it (maybe 600gph if it's drilled at the top or a siphon overflow?) (Assuming you're talking about a sump and not a closed system)

3) Look at the flow rate for the pumps you had in mind at 3.5" head.

4) Reef artists posted the flow rate reduction for SCWDs, apply that to the answer for 3.


I have a 780gph pump going through a SCWD at 3 foot head on a 40 gallon tank and it's not enough flow for my LPS/Softie tank without extra powerheads.