flow for 240 reef

[xeniaman]

do you think 4 modded mj1200(sureflow mods) is enough flow for a 240 mixed reef? My return pump pushes around 2200 gph, two of the mj1200's have the bigger prop(white) and two are the black ones.

 

[xeniaman]

anybody?

 

[coralreefer]

if the 1200 in MJ1200 insists that each has 1200 gph then that would be plenty

 

[b00st3d]

Seems like it would be a little underrated, but should be enough. For the most part we try to shoot for at least 20x flow in a mixed reef and 40x or more in a sps dominant reef.
Those modded mj1200 start out as 300gph pumps that are modded to move +/- 900gph each(real flow, not claimed). That puts you at about 3600gph of real flow. the problem with MJs is that they dont move water very far, I'd say about 24-30 inches in my own experience. And that's being generous.
That 2200gph is what your pump is rated at i'm guessing? Which means you are probably getting more like 1400-1600gph of flow once it actually pushes water up and thru your returns.
So now we take the 3600 gph of the mj's and add that to the 1600gph of your return pump and that gives you a total flow of roughly 5200gph in your 240G tank. If it's a 8ft tank you might consider putting them across the back pointing to the front to use the deflection off the front glass to help get flow thru the entire tank.
To give you a reference of flow I have 6000gph of flow in my 150G mixed reef.