How much flow do I need?

[daney90]

Hello, I have a 55 gal tank( long standard size) and I'm planning on having a sump under my DT. My problem is that I don't know how much flow I need for my return pump. Some people said around 550-850 gph and some others would recommend using at least 1000+ gph.

I'm planning on a reef tank and DIY pvc overflow if that helps.

 

[AquaRick]

Just to be clear, the return pump isn't always the only source of flow. Personally I'm a huge fan of a low flow return pump 3-5x tank volume so that your skimmer can work more efficiently. I have some reactors that T off from my return pump so i opted for a larger pump than needed for the 3-5x flow.

Powerheads in your DT make up for the total flow in your tank.

 

[daney90]

I already bought 2x 800gph power head for my DT. So how much flow of the return pump are you going to recommend?

Thanks

 

[Hondatek]

I agree with rick i prefer slower return pumps. It depends on how much your overflow can take. Do you know what your overflow is rated for?

 

[AquaRick]

I already bought 2x 800gph power head for my DT. So how much flow of the return pump are you going to recommend?

Thanks

Your return pump will also depend on your headloss (distance between the surface water of your tank and the surface water of your sump). Once you account for that I'd get something with a 200-300 gph flow rate. Take a look at the mag pumps. I'd go with a Mag 5 depending on the headloss factor.

 

[daney90]

@hondatek For my over flow I'm doing a DIY 3/4"pvc or maybe 1/2"


@aquarick I just measured the headloss and it is about 4feet.

 

[daney90]

Would a 200-300gph flow rate be enough?

 

[Grizz]

I'd go with 3/4" in min and two at that 1/2" is way to small IMO. two 3/4"s with a mag 5 will work out well if one gets plugged the other can keep up with the return pump I'm running a mag 7 with two 1" pvc over flows 4ft of head and run the return wide open i have about 600-640 GPH return flow in a 180 with a 55 gal sump, the cheato in the fuge area turns over real slow

 

[AquaRick]

@hondatek For my over flow I'm doing a DIY 3/4"pvc or maybe 1/2"

1/2 is awfully small in diameter. 3/4 should be decent on a 55g. I'd go with two overflow pipes and one return pipe (1/2" or 3/4" depending on your return pump outlet).

@aquarick I just measured the headloss and it is about 4feet.

Check out a Mag7. Has 480gph @ 4' of head loss. Odds are if you have a decent number of elbows your headloss will be closer to 5'. If you don't have too many elbows you can try a mag5. Check out reviews and see what others have done. Personally I'd probably go with a mag7 just in case you want to T off your return and run a reactor off of it in the future.