Closed-loop systems

[OodleyBoodely]

Anyone here using one for tank circulation? Had this discribed to me (at the LFS!!! This fellow, didn't get his name seemed to know his stuff) to unclutter the tank. An external pump such as a mag pump is plumbed with pvc so that water is drawn from the surface down to the pump and then returned to several differant outlets to replace powerheads for circulation. With the mag pump on a timer, a wave action can be established. The nice thing about this system, is it can eliminate the cluttered look in the veiwing area of the tank and all the circulation can be powered by one pump instead of multiple ph.

Just wondering if anyone here is using this system, how it works, and what you think of it.

[Rick O]

I know Myreef uses one on his tank.

HEY ANDY........

[Minnreefer]

I don't use one but I think that they are prob one of the prefered methods for circulation. The best way to set one up IMHO is to drill holes in the back of the tank for the closed loop, that way you don't see the plumbing and it can be directed well. HTH

Jon

[Doug1]

Mojoreef uses one on his 300 gal tank as well.
My 75 is drilled with 2 one inch bulkheads, I am going to hook the amg 18 to one and have it fed a pvc manifold with 3-4 adjustable returns, eventuall switching a couple to sea swirls, and the other BH fitting will drain to the sump and be returned by a mag 5 at about 400 gph, slowing the water flow thru my sump, increasing dwell(contact ) time for a skimmer or a macroalgae fuge.
'I have a 55g sump and the high flow rate throws salt creep all over and lots of bubbles

[cichlidite]

sounds like a good idea to me, as I already have an issue with not enough outlets and powerstrip capacity.

[OodleyBoodely]

I'm giving it some serious thought for my 55. I'm thinking of using flexible hose instead of pvc-don't want to mess with the pvc. I don't have a sump or a drilled tank, but, I still think it could work. I'd just have the return line split to both sides of the tank, perhaps even to 4 outlets. Also, I could rig a smaller line with flow adjustment to my refugium which could cut out one more ph there as well, only problem with that idea is that the ph in the refugium also operates the venturi to the siphon return. I'd hate to lose that added safty check-I've already flooded the room twice when the siphon return lost siphon.

What do you use on the ends of the return lines to direct the water flow? Any ideas on some low-profile return gadgets? Remember, I want to eliminate as much clutter/gadgetry as possible. Would spray bars work? How about a good strainer idea for the intake hose?

[TroyF]

I've got an Ampmaster plumbed in a closed loop and I really like the flow without all the PH everywhere. I looked at running multiple Tunze powerheads but cost was a factor. I figure in the configuration I have I'm probably getting ~1500g/h out of each of the returns and it leaves very few dead spots in my 155gal tank. There are still a few though and I may end up adding one more return to a lower region in the tank.

[Doug1]

Oodley look at the strainers I have on m overflow, those are standard sized and will fi common sized bulkheads. The whole point of a closed system is the water is drawn from subsurface and pumped directly to a return fiting or manifold, ie it goes from tank, directly back into the tank, wheter the return fitting is drilled and plumbed or runs over the top and directed by "Line Loc fittings (prefered) what makes it a closed loop is that when the power shuts off the drain will raise water level in the plumbing to equalize with the tank level. Since the intake is lower than the return(or not) there is no siphon action like you get when the BH drains into a sump and is returned to the tank by a seperate pump.
The open area between the drain and return is what makes it an open system subject to siphoning and all that
In a closed loop system if the power goes off the water in the retrn lines are either below the tank surface level(driled return) or the return pipe going over the back drains down to match the level in the tank, it has no where to siphon off to like a sump
Is this making sense
?

[balakoth]

Great Thread! I had never known exactly what "closed loop" system ment. Now I do, and Now I want one. So basically you create a semi overflow with your PVC, it travels down to your External pump, which then pumps it BACK up to several returns.

Questions: How many returns can you create or is that simply limited by the pump and head loss? I myself would like more information on this as well.

I dont suppose anyone has a Diagram or example sheet that they could show us to demonstrate good plumbing techniques for this type of system?

I have 4 MJs in my Tank right now including the Rio that powers my Skimmer and its Return. Its cluttered and it annoys the poo out of me.

I would love to be able to have at least 900 gph flow in my tank with 2 Returns. Does this seem like a possibility? I might stick with the 900s to create spray bars at the bottom behind the liverock, but boy would that solve alot of my display issues.


Thanks for starting the thread Oodley Im on the same route as you, No drilling! Of course if I intend to use a sump in the future would this all be wasted effort? As I could be doing this with my Sump return.


- Joe

[Minnreefer]

The great part of a closed loop is that it has nothing to do with a sump so you can get as much flow as your tank/ pump will allow.

[Doug1]

The draw back is you will need a hole drilled for the pump to draw thru
I am going to use one of mine for the loop and a much slower flow rate ti the sump

[steveweast]

I jumped on the closed loop bandwagon about 2 months ago. I used to use 12 powerheads in my system for circulation. I replaced those powerheads with (4) ampmaster 3000's. I retrofitted the closed loop without any drilling or even turning off the main sump pump for that matter. I just created an intake cage for each ampmaster out of eggcrate. This eggcrate cage was then lowered into the tank next to each overflow. The out-take was then split into three directions. These outflows were then distributed throughout the rockwork. Each was hidden as much as possible and terminated behind,under, and in front of the rockwork. The biggest hassle throughout this was dismantling the upper portion of the reef to accomodate the closed loop system...but, it only took about 4 hours and is well worth not having to clean powerheads again. If something happens to one of the ampmasters, it's really easy to access and service now. Pictured below is a shot of the intake and out-take lines for two of the four ampmasters.

[steveweast]

Here's a picture of one of the camoflaged return jets....it's in the upper right hand corner.

[Alice]

I was hoping you were going to show us a pic of your tank Steve! Wow! I really can't even see the return; it must be heaven to be rid of all the powerheads.

[balakoth]

Originally posted by steveweast
....it's in the upper right hand corner.

Uh.. if you say so... Might I add a comment about your tank.... WOW