[waynedejno24]

This is the first big tank-350 gallon-I've started. I have 2 overflows 6"x12"x6" with 2" bulkheads. My pump can do 7500 gph, question is are my overflows going to keep up? Or do i need to add another one, I have plenty of room.

[e_baer]

what size are the bulkheads?

[NATIVEVAMAN]

I dont think 4 overflows will keep up with a 7500 gph pump.Even if you have two 1 1/2 drains thats only 2400 gph for both drains together.Get a reliable head flow chart and find two pumps that closely match the max drain flow.

[waynedejno24]

e-bear there is a 2 inch and a 1 1/2 in each overflow....i do have room to run the returns behind the tank. I left 4 inches of room in the wall for things like this......I have been told the 2 inch drains are enough but i dont know if the overflows are big enough to keep up..

This is the first BIG tank, always had 125's or 150's. So i want to make sure i am doing it right the first time.....

Nativeman I got a Dolphin 7500/6500 return pump for almost nothing...i needed a pump that could pump 20-25 feet. Because the filtering system is in the basement.

[NATIVEVAMAN]

With one 2 inch drain you will get slightly under 2400 gallons per hour.I would love to put my return and fuge downstairs but the woman that lives there would not like it lol.

[e_baer]

20-25ft? the max head on the pump is 22.25ft.

Dolphin 7500/6500 Amd Master External Pump (Saltwater Aquarium Supplies > Water Pumps > External > 2000 GPH and higher )

[waynedejno24]

i just remeasured, i'm at 19' 8" lol

[e_baer]

well, even that, it is gonna greatly reduce the pressure. plus, you throw in a few 90 degree bends, it may only be pushing a few hundred out by the time your done.

[waynedejno24]

ok, i have never set up a closed loop system. but if i do so do i need the 10x turnover in the tank through the sump system?

Like i said i want to do this right the first time, so time and $$ reaaly dont matter if i can save the frustration.

[waynedejno24]

According to dolphons website at 20 feet it still will do 3000gph, but that still is not enough. or will the closed loop solve this? I am use to putting everything under the tank and not have to worry about head feet or lose of flow.

Two returns pumps? what would you guys recommend?

[NATIVEVAMAN]

Most often closed loop systems get there water from a bulkhead in the back center of the tank. Some people have tried to feed them from a seperate overflow but they cause some pretty bad micro bubbles.I would caution against the use of actual elbows as they can and will cause cavitation,instead use street elbows that have rounded interanal corners.Even better if yiu have the space use sweeps.Also in your case having the closed loop pump on the same floor as the tank would be an advantage.

[waynedejno24]

Native- i have room to add a third overflow in the back of the tank for a CL. my question i guess is will a closed loop enable me to cut the flow back from the sump to the 3000ish? Its close to the 10x, plus the CL system.

I can move the sump system within 10 feet to, just gunna be harder to maintain. Have a Half basement, part under tank is four feet deep. Was planning on running stuff to 8 foot section of basement, but can move to the 4 foot section just have to buy a ladder...LOL and duck.

I also have to do more research on the CL system.....

[pogodzib]

I'd push as much flow through the closed loop and keep the flow through the sump minimal. Sumps actually function better with lower flow rates since your skimmer and macro algae will have more time to remove the organics. Besides, what do you think will happen if your closed loop pipe gets plugged? Now, what would happen if one of your overflows would get plugged?