Closed loop design help needed

[tone51057]

I'm interested in information on closed loop design (hard plumbing). Never done this. Trying to decide if I'd like to attempt this on a 100 gal tank build I'm about to start. I'm experienced in the hard plumbing. Just would like to see how others have done this. Pics and descriptions would be helpful. Can't seem to find a sticky on this. Thanks

 

[Simply__J]

I hard plumbed my 55 gal considered doing a closed loop. Opted out because I wanted the flexibility of pointing the flow from the return as I please, depending on my rock-work and such. I would suggest you use a lot of unions. I just added a ball valve in order to install my new UV sterilizer.

 

[dvskin]

Ran a few closed loops. The biggest thing you have to remember is.... There is no going back. Planning is key.

 

[Rob Top1]

Just finished plumbing mine. Give me a day or two and I will get you pics. I love CLs. Only thing I would change is were I drilled the feed hole. Dead center sch 80 2" BH...not the easiest to hide but I have some ideas.
My CL is running a Reeflo Barracuda with an ocean motion 4-way. Two left side two right. Top and bottom. The bottoms have double Y loc-line so they both have 4 exit points giving me a ton of flexibility. The top side is just single outs. Plan the hole location as there arnt take backs. If this is a glass tank keep in mind drilling it may result in no tank at all. Even though I had drilled better than a hundred holes when I pop mine in I was sweating bullets. It is possible to create an over the top feed for the cl if you really want it but are afraid to drill. Lmk if you want those details and I will share

 

[Rob Top1]

 

[Rob Top1]

They loaded in reverse order. So bottom up...
Back of tank with 2" spa flex heading under stand
Under stand were that spa flex meets the hard pipe. You'll note union and valve at both ends of the feed. There is a lot of water in that pipe, should I need to change the pump of plumbing I wanted to be able to remove a section with out cutting. Also flood your pump meaning use 1 size larger pipe up until you get to the pumps intake. The pump has s 1.5" intake so 2" I'd used up yo the pump
The second photo is the pump room CL pump is on the right with the OM 4-way
First pic which was ment to be the last is the tanks right side, left side is the same.
Decided to give you the cruddy pics instead of making you wait

 

[tone51057]

Thanks for the responses! With what I'm seeing, flood prevention comes to mind, considering the low returns and overflow. I see one response has a check valve in line. A lot of people say they fail in time and I would assume they have to be taken off periodically to clean. I would also like to be able to alternate flow and rate from the returns. Any suggestions? I may have to experiment on an old tank to see if I want to attempt this on the 100 gal display. Would like it to be bullet proof, if possible. What about maintenance on your CL? Thanks for everyone's time. Appreciate the help. Tony

 

[dvskin]

A true closed loop will not need check valves. There is no back syphoning, because the system is closed.

As far as alternating flow, that's what his Oceans Motions 4 was is for, it's a 4 way valve with a drum in the middle the rotates and alternates flow through each outlet.

As for the maintenance, that's where the unions n ball valves come into play. It allows for removal of pumps for schedule PMs.

 

[Rob Top1]

A true closed loop will not need check valves. There is no back syphoning, because the system is closed.

As far as alternating flow, that's what his Oceans Motions 4 was is for, it's a 4 way valve with a drum in the middle the rotates and alternates flow through each outlet.

As for the maintenance, that's where the unions n ball valves come into play. It allows for removal of pumps for schedule PMs.

That's the ticket

 

[Rob Top1]

Again not the best pic...a work in progress however it helps to illustrate the alternating flow. The Ocean Motion four way send water in a one minute cycle from bottom left to top right, top left to bottom right. Thus giving alternating flow.

 

[tone51057]

Yea I don't know what I was thinking dvskin. Not enough coffee this morning I guess. I'll check out the Oceans Motions 4. I do always use unions and ball valves at pumps for PMs. I noticed the pumps used are higher flow. I guess it depends on what flow rate you're you want, size of tank, and how many returns. I'm wondering if this is practical for a 100 gal display, or is this more suited for larger systems. I do like the idea of reducing the hardware in the tank.

 

[tone51057]

Thanks for the pics Rob Top 1. Nice! What size tank is that? I guess I could drill for the lower returns and run loc line right off the bulkheads. For the upper I have two Sea Swirls I was thinking of using.

 

[Rob Top1]

My pleasure. Kind of a sneek peek here as I am biting at the bit to start my build thread but feel I need to get s little farther before I start it. The tank is only 240, biggest that I could get down the stairs.
A CL can work well on any size tan . I would argue the smaller the tank the better the idea. You have less space for other water moving devices.

 

[AKTank]

Here is a return that I used on my last tank. I needed to be able to point the flow in any direction so I put T's all the ay around the return loop with slip caps in the ones I wasn't using. I stuck one of the lock line returns in for this picture. I used 4 in various positions at any given time. With a bigger pump I could have used more. You can see the bulkhead fitting in the back/middle of the tank. This was the intake leading to a pump behind a wall. I had a strainer on the inside of the tank that threaded into the bulkhead. The return came back through the wall with flexible vinyl tubing. It's ugly but I had a custom canopy that hid the plumbing and lights. All that was visible inside the tank were the black (and later pink) return nozzles.
Hope this helps.

 

[MarineREEFpassion]

I'm interested in information on closed loop design (hard plumbing). Never done this. Trying to decide if I'd like to attempt this on a 100 gal tank build I'm about to start. I'm experienced in the hard plumbing. Just would like to see how others have done this. Pics and descriptions would be helpful. Can't seem to find a sticky on this. Thanks

So I did a closed Loop on my 150 a week ago and am not liking the results much, in regards to the flow rate out of the UV light. Unless you drill a hole in your tank to have direct access to DT water you’ll end up using a bunch of elbows as I did and well my pump that’s rated for 3170 GPH only puts out 647 at my flow sensor. I was shooting for 1700 minimum for bacterial/algae prevention and I’m way off that. I ended up using 8 elbows which sucks, but w/o a hole in the side of my tank that was my option, and with the short runs I have I’m still putting on around 18.5’ HP which is obviously robbing the flow rate a lot. If I can’t figure out a way to get more flow I’ll scrap the so called closed loop and go from my sump to the DT, which would suck cause I like the CL concept.
It’s also kinda frustrating there’s not a lot of good quiet pumps out there that are rated around 5000/7000 GPH under $500 that I figured I’d need to get the rate I want with the current set up. I hope you have better luck lol.

 

[mfinn]

I did a closed loop on my 233 gallon tank.
It has a 1-1/2" suction bulkhead about 10" off the bottom on the back wall.
I made a horizonal return manifold, with 1" risers going to 4 bulkheads on the back wall.
2 middle level and 2 lower level.
On the inside I used a 1" to 3/4" bushing with a 3/4" locline splitter going to two 1/2" loc-line nozzles.
This sends water in 8 different directions in the tank.
The pump sits under the tank along side my return pump.

 

[MarineREEFpassion]

I did a closed loop on my 233 gallon tank.
It has a 1-1/2" suction bulkhead about 10" off the bottom on the back wall.
I made a horizonal return manifold, with 1" risers going to 4 bulkheads on the back wall.
2 middle level and 2 lower level.
On the inside I used a 1" to 3/4" bushing with a 3/4" locline splitter going to two 1/2" loc-line nozzles.
This sends water in 8 different directions in the tank.
The pump sits under the tank along side my return pump.

Awesome thanks for the reply. Nice set up! Looks good m, when I get my new tank I’ll definitely drill a hole in the back for a dedicated line for the UV pump which will cut a lot of elbows and HO off since that’s my biggest issue. I had to pull from the tank back to the tank without putting a pump inside my DT which is my issue. I’ll end up plumbing it from the sump up to the tank until I get my new tank. Thanks again for your reply and a pic of your set up. It helps a lot!

 

[joelbegt]

I run no powerheads using a Reeflo Dart for my closed loop using two 2” inlets and six 3/4” outlets along the bottom. I really want to build an alternating valve to randomize flow a bit In the future, but I’ve learned a few lessons for the next closed loop.

My left side outflows my right and I should have stepped up in size on my long runs to equalize the flow

Low profile inlet covers don’t reduce the suction enough using a dart with two 2” inlets and I lost a few fish in the beginning.

 

[MarineREEFpassion]

I run no powerheads using a Reeflo Dart for my closed loop using two 2” inlets and six 3/4” outlets along the bottom. I really want to build an alternating valve to randomize flow a bit In the future, but I’ve learned a few lessons for the next closed loop.

My left side outflows my right and I should have stepped up in size on my long runs to equalize the flow

Low profile inlet covers don’t reduce the suction enough using a dart with two 2” inlets and I lost a few fish in the beginning.

Nice set up! Thanks for your ideas and for sharing your pictures I appreciate it. Great ideas from everyone.