closed loop confusion

[an411]

I have been trying to find out what the advantages of a closed loop is I know that it has to do with the plumbing. From what I have observed it allows for more water movement with more returns. Am i right? Also do you need 2 overflows to accomplish a closed loop?

 

[amike5]

A closed loop doesn't use an overflow. It sucks water in from the tank through a pipe and spreads it over multiple outlets back into the tank. The pump has no head pressure because of being a "closed loop" and therefore the pump you buy should be the actual volume you want. For instance, my closed loop sucks in water from the tank through a 1 1/2" pipe into a 2700gph pump. I have a total of 8 - 1/2" outlets, 4 on the bottom and 4 up top. The pump output goes into an oceans motions so that no more than 4 of these are open at the same time providing a random flow to the tank.

 

[papagimp]

You'll still get some headloss, after all, gravity counts.

It's just another way to provide flow without the use of powerheads in the tank. Helps keep added heat out of the tank. And most powerheads don't push what the external closed loop pumps do. Unless you wanna spend the extra money for a Tunze or Seio.

I wouldn't say it adds more flow to the tank. You can have 2000gph running in a close loop or run 2000gph in powerheads, both give you the same flow. It's just another option, that's all.
Looks better in my own opinion though, none of those bulky powerheads hanging in the tank looking all sorts of ugly.

 

[an411]

Wow I was way off I thought that it had to do with the overflows and how the water was distributed from the return. So you need another pump to circulate the water through a closed loop and that is all that it is. From the picture that i saw the person had it under the sand bed with 4 returns sticking out. I might have to look into this more. I agree I think that it looks cleaner then the powerheads and I am sure in the long run alot less cleaning and money. Those good powerheads are not cheap.

 

[vr697getta]

this site hepled me when i built mine
http://melevsreef.com/how_to_build.html

 

[amike5]

Yah, besides all the additional plumbing you have to do. Especially if your tank isn't drilled for it because you then have to run your piping over the top of the back to get it in there.

 

[papagimp]

for a closed loop, all you need is a hole in the tank, going to a pump, and a hole in the tank, coming back from the pump. Wa-la, a closed loop system. It doesn't have to have multiple returns or anything. Just one pump pulling water directly from the tank and going back in. Overflows are used for sump/refugium set ups. Not closed loops. People using multiple returns from their closed loop do this as a means to spread the flow around, not because they have to. Allows for more customized water movement.

 

[an411]

my tank is drilled for a return and overflow so basically I would not have the return just end at the top of the overflow I could just continue it anywhere and have multiple returns correct?

 

[Gobydood]

Take a look at this. This answered all my questions about closed loops, plus I like the SCWD, have one on my return.

http://www.melevsreef.com/closedloop.html