Dual Return Bulkhead question

[ron2morales]

Im in process of planning a custom tank and going to have a ghost overflow in the center of the tank. I want to have a return on each side of the over flow. So I guess a dual return (not sure if there is a specific name). I would like to know what size of bulkhead should I have for each return. This would be for 100gallon tank.

 

[thegrun]

3/4" would be fine. You could probably get by with 1/2", but I would use 3/4".

 

[sfdan]

Assuming you wanted somewhere between 3x (lower end) - 10x (really high) turnover, that is 300gph-1000gph. I think you could almost squeeze 1000gph through a single 1/2" pipe if you really wanted, so technically speaking either size is fine. Realistically though if you want 10x turnover I'd suggest 3/4".

However assuming you stay within the "normal" range of tank turnover, 3-5x, that is a maximum of 500gph divided by 2 returns = 250gph per return. That could easily be handled by 1/2" with tons of room to spare. Technically you'll have more flow with 3/4" since there will be less head pressure, but otherwise either will work fine. There are loc-line fittings for both 1/2" and 3/4" if you choose to use that for aiming your return flow.

Personally I use dual 3/4" returns on my 120, though I have a very low turnover tank so I could easily have 1/2".

 

[nereefpat]

+1 for 3/4.

 

[billdogg]

Either will work just fine. Please do remember to have the outputs close to the surface so that if (when) the power goes out the tank will not drain down too far and cause a flood.

 

[rocsec1]

I used 3/4 and it works well for me.