closed loop system

[polarbear]

I was wondering who had one of these on their tank (100 plus gallon). Is it worth doing or will circulation pumps be just as good. I was watching a clip on the web where a person had a nice one set up with the rotating ends that change the direction of the water all the time. Is there any large benifit of having one besides water movement?

[Zarathustra2]

There are a few benefits of CLMs.

1. Easy turbulent water flow.

2. Lower heat output as you use one efficient pump instead of several innefficient powerheads.

3. Lower power usage """""""

4. You can put in an in-line SCWD or those rotating nozzles from hydor for even more turbulent/wave like flow for much cheaper than a wavemaker.

5. They are very cheap!!!

6. Generally more reliable than powerheads

Downsides

1. If you don't like PVC work its a pain

2. You really need to plan ahead. You can't just move a powerhead.

I don't think i would put in the work for anything but a very large tank (125 or greater.) I have a simple one set up on my 90 that is part of my rockwork, But i still use powerheads as the primary water mover.

Wetwebmedia has a great article on them. http://www.wetwebmedia.com/pbh2oret.htm

[Derry]

I've got a closed loop driven by a Reeflo Dart (Snapper? The smaller of those two), with four outputs controlled by an OM Super Squirt. There's definitely stronger and more random water movement when it's running. To watch the food particles in the water column, I get some really complex interactions between the water movement created by the closed loop and the water moved by my two K4s and return pump. I don't know that I'd list a closed loops as a gotta-have, but I know my big tank (140 gals) looks "happier" when the closed loop is running.

[Gonzobob]

Also keep in mind that like many other systems close loops can go from fairly simple to very complex. Melve's reef has a writeup on a small one involving a pump some PVC and a SCWD. It' the basis for one I'm putting on LSK's 46 bow front. I liked this approach as it didn't require a large investment in time or money and no drilling was needed.

I've also seen some very impressive setups with complex systems involving Ocean Motion setups, high end pumps and tanks drilled on the sides back and bottom glass.

In the end it boils down to what you want to achieve and what you're willing to invest (time / money)

Complex / turbulent current is considerably better then liner current for most corals and fish but the level that you want to pursue is negotiable.

[polarbear]

Gonzobob. is there anyway to see the ones you are talking about? i was just thinking about puting just 2 outlets, one on each side of the tank in the front

[polarbear]

I've got a closed loop driven by a Reeflo Dart (Snapper? The smaller of those two), with four outputs controlled by an OM Super Squirt. There's definitely stronger and more random water movement when it's running. To watch the food particles in the water column, I get some really complex interactions between the water movement created by the closed loop and the water moved by my two K4s and return pump. I don't know that I'd list a closed loops as a gotta-have, but I know my big tank (140 gals) looks "happier" when the closed loop is running.

do you have any pictures so that i can see what it looks like? if you dont mind

[Tim and Kendra]

Here is some pictures of a really detailed close loop that I found in a article. When I upgrade to a bigger tank I plan on going this set up or something like it.

Fish tank.bmp

Fish tank2.bmp

[Zarathustra2]

Gonzobob. is there anyway to see the ones you are talking about? i was just thinking about puting just 2 outlets, one on each side of the tank in the front

I would just get a couple of powerheads and use a spraybar instead. For a CLM to be worth it you generally want to be looking at 6 outlets (or more.) 2 in front and back and one on each side. This helps with any deadspots ect. Short of that i would just use a spraybar with a SCWD. Put two nozzles on each side of the tank and have the SCWD alternate them. Cheap wavemaker right there.

[GKarshens]

I used to run one almost identical to Melev's. I actually copied his design. I agree that on a large system it is probably the way to go. When I build my 240g I am planning on implementing a pretty complex closed loop to be the main if not total water movement device. The main reason I am going that route is I don't want to see any equipment in the tank. Not to mention it is cheaper on a tank that size.

[Gonzobob]

Here's the small SCWD based closed loop: http://www.melevsreef.com/closedloop.html

[Stephen]

i built my closed loop just like melevs and it works very well. i dont even have a scwd