sump pump question

[Melonbob]

I have been researching this for a bit, and you can't get two people to agree completely on the subject. What I ended up doing was going with 1800GPH for my 180, which in theory is 10x, but then take away the head loss, and I'll likely be closer to 1300gph. I figured this was fast enough to move some serious water, but still slow enough to allow the water to be skimmed and spend some time in the fuge. The balance of flow I will be doing with powerheads, cause frankly, over the top closed loops are fugly.

[sicklids]

okay, now what is a closed loop? i have read peoples post on these and have no idea what they are

[RyanG]

Its a system where you drill a larger hole for a pump intake plumb it to a pump and return the water from to several smaller smaller holes also drilled into the display. Its a way to get good circulation without using powerheads. Keeps the system clean looking.

[Melonbob]

So long as you are ready to drill a bunch of holes in your tank.....otherwise, you can do the same thing with a loop of pipe over top of your tank.....IMHO waaaay fuglier than a couple of powerheads

[Rcpilot]

Closed Loop:
http://en.wikipedia.org/wiki/Closed_loop

http://en.wikipedia.org/wiki/Reef_aquarium

"To create turnover many reef aquarists use an Overflow (internal or external) which drains water into a sump where it is then pumped back into the tank. Tanks that come equipped with an internal overflow and pre-drilled holes are known in the hobby as "Reef Ready" or simply "Drilled" tanks. Of the many methods of creating the required flow, one of the most popular is by using multiple powerheads[citation needed] which are simply small submersible water pumps. The pumps may be randomly switched on and off using a wave timer, with each aimed at the flow of another powerhead or at the aquarium glass to create flow in the tank. Another method gaining popularity is the closed loop in which water is pulled from the main tank into a pump which returns the water back into the aquarium via one or more returns to create water turbulence. Only recently available commercially, submersible propeller pumps are gaining popularity due to being able to generate large volume of water flow (turbulent flow) without the intense directed force (laminar flow) of a power head. Propeller pumps are more energy-efficient than powerheads, but require a higher initial investment."

[Rcpilot]

Closed loops done with drilled holes are the ultimate in look IMO. I HATE the powerheads in my tank. Now those are fugly.

The basic design is to buy a big pump that will do the turnover you want in pure circulation. In a 120g tank, I'd be shooting for 2000GPH as a minimum. I'd REALLY want closer to 3000GPH.

You use a big bulkhead, like 2" or 2.5". You drill the bulkheads UNDER the water level. Like in the middle of the tank. Whatever the size is on the pump intake--do the outlets on the tank AT LEAST that big and even bigger is fine. I've seen people drill 2 holes 2" each and pipe them into a pump. Don't restrict your intake.

Then you build a manifold on the outlet of the pump and drill 6 or 8 or 10 holes in the back of the tank and plumb each line off the manifold with a bulkhead. Line-Locs are flexible tubes that you can connect inside the tank to direct flow in various area or configurations.

There's no head loss because all the intake and outlets are under the water. The pump is just in the middle of the loop. Closed loop.

Search Reef Central in the equipment forums. People have done some COOL stuff with reef controllers and solenoid valves.

I think the only thing better than a closed loop would have to be a closed loop with a surge tank.