Closed Loop Question

r3k2p

New member
So I'm working on the plumbing for my closed loop:
Reeflo Dart
Ocean Motion Super Squirt

The previous owner of the closed-loop had a total of 6 lines back to his tank. The way it was setup is 2 go out to the side which are constant, and the Super Squirt. All reduced to 1" after the 1.5" 4-way, there will be about 3.5' of pipe for each constant, and 1' to the Super Squirt... then about 2.5' - 3.5' from each outlet on the Super Squirt. How should I calculate the head pressure? Should it be the 3 sections, 2 constants and 1 to the Super Squirt? or all 6 outlets? Will there be enough output to support the 3600 gph of the Dart? Should I add another constant?

Feeding the dart are 2 drains, 1.5" and 1" that I'll have to find a way to combine to go to the inlet of the Dart. The tank came from someone else and I think the previous owner of the tank used the 1.5" to feed the closed loop and the 1" for the return back into the tank... I've decided to use both holes for the drain and go over the top for the returns. Does anyone know where I can find a 2.5" "Y" locally?

With the 6 returns on the closed loop and 2 from the sump, I'm going to have 8 returns over the top of the tank. This is my first closed-loop setup... I'm excited to not have to add power heads but I don't want to go overboard.

All replies and recommendations welcome... and thanks in advance...
 
?? That sounds a little crazy.

I run a Sequence barracude on a OM 4way(pretty much the same thing as your just larger) My OM sits about 5' above the pump + all the bends and turns involved. Since the Squirt is only 1" pipe it will be reduced down and cause a little more friction on the pump. Your head loss should be calculated from the Pump outlet to the Squirt (than you can figure the amount of GPH coming out of each outlet after that) remeber a 90 counts as 1' of head less and a 45 counts as a 1/2'.

You should only have one 1.5" feed to the Pump it self and a 1.5" out to the Squirt. Than 4 lines that dump back into the tank. I would just cap off the other hole for now rather than tying in to the pump feed. Having 6 returns off the Squirt is really a waste IMO.

What are the demension of the tank and where do you plan on having the CL returns dump back into the tank at?

I have a Pennisula set up so I have 2 CL returns that dump in over the top of the over flow box and 2 more that run the length of the tank and dump it at the end spraying back towards the over flow box. I get about a 1/2"+ wave at the top of my tank from this and love it!
 
First of all you should run 2" feed's into the intake of the Dart then 1-1/2" out to the Ocean motion what you do on the out let's of the Ocean motion is up to you.
As for head loss it's ZERO on a closed loop.
(Per Chris @ Reeflo)
 
Everything they said is right. Your original post is extremely confusing. It sounds like you're trying to compute something when you don't need to. I have more 90's than I want to count and about 60' of plumbing in my closed loop and I have MASSIVE flow from my Barracuda. My setup sounds almost identical to Rob's.

Don't forget to use a LOT of double union shutoffs so that you can remove any component of the system. Let me repeat that because this is the most important point. Be absolutely sure that you have enough shutoffs and unions in place that you can easily remove the pump or the OM from the system without having a headache. Murphy's law is in full effect.

And I still have a Tunze 6100 and a pair of Koralia Evo 1400's just because I identified dead spots and was able to improve the flow a lot in this way. I get a lot of flow from the closed loop, but it was better with them and the Tunze works great on my battery backup.
 
You should only have one 1.5" feed to the Pump it self and a 1.5" out to the Squirt. Than 4 lines that dump back into the tank. I would just cap off the other hole for now rather than tying in to the pump feed. Having 6 returns off the Squirt is really a waste IMO.

What are the demension of the tank and where do you plan on having the CL returns dump back into the tank at?

I have a Pennisula set up so I have 2 CL returns that dump in over the top of the over flow box and 2 more that run the length of the tank and dump it at the end spraying back towards the over flow box. I get about a 1/2"+ wave at the top of my tank from this and love it!

My concern about tying in the 2 drains is that the Dart is 3600 gph and the drain/overflow calculator on the home page says for 3600 gph you need 2.5".

I'm sorry if my explanation is confusing... I don't have 6 running off the Squirt. On the outlet of the Dart before the Squirt there is a 4-way. 2 go out to the side which are constant and the last going up the the Squirt(splits to the 4).

First of all you should run 2" feed's into the intake of the Dart then 1-1/2" out to the Ocean motion what you do on the out let's of the Ocean motion is up to you.
As for head loss it's ZERO on a closed loop.
(Per Chris @ Reeflo)

The Dart has a 2" inlet so I was going to reduce the 2.5"(combining the 2 drains) down to 2" to go into the Dart.

Then back to the tank, the Squirt is 2600 gph. If what you're saying is correct about head loss(per Chris @ Reeflo) then I need the 1000 gph which is T'd off before the Squirt or there will be back pressure to the pump. If this is true, it answers my question... no need to add or remove any of the outlets.

It's 1.5" to the 4-way cross, then it reduces down to 1" to all 3 outlets... The Squirt has a threaded 1" inlet. Should I not reduce it to 1" until right before the squirt?
 
Whoa, hang on a second. You're confusing overflow numbers (what gravity can do) with pressurized numbers. The intakes for the closed loop are going to be submerged and those holes should not be in some kind of overflow box. They have to be directly open to the tank water and far enough down in the tank that you don't get suction to the surface. You can push a lot more than 3500 gph through a 1" pipe if you put a big pump behind it.

Can you please post a picture of the tank in question so that I can understand where the holes are?

Here is the overflow end of my tank:

2612353540038763404S600x600Q85.jpg


The two holes further out are the closed loop intakes and the two holes in the middle are the overflow holes. Here you can see it under construction:

2888579380038763404S600x600Q85.jpg


And here's an almost perfect shot where you can get an idea of the plumbing:

2950072580038763404S600x600Q85.jpg


Note that the intakes have plugs in them at this stage in the process. I needed to leak test the tank.
 
As you can see in the picture, I only have two 1" intakes for the closed loop:

2681732100038763404S600x600Q85.jpg


I get a LOT, LOT, LOT of flow out of it.

This is my return and OM setup under constrution:

2987317090038763404S600x600Q85.jpg


Note that the two 1" closed loop intakes T together into a 1.5" pipe which is the largest pipe I have in the closed loop system. I can't emphasize enough that I have a LOT of flow from the closed loop.

All that said, you will have a nightmare with weird things happening if you try to branch the closed loop off and have part of it go through the OM and part of it not. Every time the OM transitions it's going to create all kinds of weird pressure situations for the other lines. Everything should go through the OM. Now.. all that said, I removed the barrel from the OM 4-way and just have it wide open to all four outputs. I like that situation the most. My OM broke and I decided I liked it better anyway.
 
I'll get a pic up soon... camera battery needs charging. Both 1.5" and 1" holes are on the bottom of the tank, both about 3" from each other, 2" from the back. Here's a diagram of the top down view. the solid line is the rear pane and the shorter dashes are the front.

______________________________________
| O o |
| |
| |
| |
| |
| |
--------------------------------------------

Ok, that makes sense... since it's under water and pressurized from the gravity of all the water in the tank, the 1.5" will provide enough flow to the Dart so I can just close off the other 1".

Currently there are unions and ball valves at all junctions before and after the DART and only unions after the Squirt. Thanks for the tip for the eventual need to remove the pump... should I be thinking about adding ball valves to the outlets of the Squirt too?

I was planning on getting a new barrel if/when the Squirt goes down to the version that opens 2 at a time... but maybe I'll go with what you did and just remove the barrel completely.

Sorry for being so confusing... I really appreciate the help.
 
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Ron, yours is identical to mine except my OM sits in My canopy above the tank so I don't have as many valves as I wanted to have.

Use what ever size plumbing your Pump is designed for on the feed side ( drain from tank to pump). If you have to reduce it down do it on the returns going back into the tank and right before the OM Squirt. Now as for the "extra" flow you are trying to divert. Some one correct me if I'm wrong but you can "tee" off the return back to the OM and make yourself a Manifold that you can use to feed a Recirc. skimmer, reactors, etc. Never done it before but I don't see why you could do it. You would need a large enough sump or a lot of baffles though as there may be a lot of water movement through the sump.
 
just noticed the diagram i tried to make didn't work... the side dashes are suppose to be inline with the top and bottom lines... and the holes are suppose to be centered.

Ron- the current setup is very similar to yours. The only difference is there is a 4-way cross before the Squirt. I'll just cap the lines and only use the outlet going to the Squirt.

My concern was that if I capped them, there would be too much back pressure on the pump making it work harder than it needed to... 2600 gph OM Super Squirt vs. 3600 gph Dart. I was thinking it would be like trying to blow air through one of those coffee stirring straws.
 
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You're a lot better off T'ing off of the return pump rather than the closed loop pump. It's no longer a closed loop if you do that, and it just doesn't seem to me like a good idea.

If it works for your design, you may wish to add a drain to the output side of the closed loop if that helps your water change system.

You'll be perfectly fine with a 1.5" feed. If your barrell in your squirt only outputs to one at a time then you won't have the flow you're looking for. I very carefully modified my drum after talking to the guy at OM.

2251732300038763404S600x600Q85.jpg
 
just took all the plumbing apart to inspect the barrel of the Squirt... it has 2 holes opposite each other.

for the overflows, there are 2 holes with 1" bulkheads drilled about 4" from the top and 10" from each side. currently there are 2 overflow boxes that attach to them. my plan is to make a coast-to-coast overflow box to drain into both holes... another thought but not really planning is an external box.
 
Ron- after rereading your reply about being able to push more than 3500 gph through 1.5", I guess it should be the same for 2- 1", right? So although the OM Squirt is rated for pumps up to 2600 gph, I should be able to get the full 3600?

As far as adding a drain to the output side, where do I divert the drain to?
 
You "divert the drain" to the sewer. It's a really easy way to take water out of the system. Again, depends on your planned water change method.

Schedule 40 pipe
Dia. inches: Cubic ft/min: Gallons/minute:
1/8" 0.0004 0.003
1/4" 0.0007 0.005
3/8" 0.0013 0.010
1/2" 0.0021 0.016
3/4" 0.0037 0.028
1" 0.0062 0.046
1 1/4" 0.0104 0.078
1 1/2" 0.0141 0.106
2" 0.0233 0.174

I think you're getting way too caught up in gallons per hour. An OM 4-way would be better for your application than the squirt. I think that it's probably entirely unnecessary and you could just ask easily go T and then T and get the desired result without an OM product. That is essentially what I am doing now and I could have saved $300 and not gotten the OM 4-way.
 
I see... drain so it automatically does water changes... incorporating an ATO to refill the saltwater? sounds like something i'd like to somehow incorporate...

I agree, I am way too caught up in the GPH... I'm trying to utilize the equipment and plumbing I already have but make sure it's set up right before installing it on my system.

check this out... just did a search on the Ocean Motion site forums...
http://www.oceansmotions.com/forum/viewtopic.php?t=559&highlight=dart
 
OK, cool. Do that. Paul is the expert.

I wouldn't recommend leaving that output open and counting on an auto top off to refill it. I'm just saying that if you want a way to open a valve to drain water from your tank, that's a great way to do it.

I think if you want to put bulkheads in both openings and tie them together to allow for more possible water into the input on the Dart, now is the time to do it so you'd might as well plumb them together into pipe the same size as the Dart intake.
 
I wasn't thinking about leaving an open drain from the tank... i was thinking that i might be able to set up a timer to remove and refill 'x' amount of water every so often. probably thinking way too much again...
I like the idea of having a valve to open and drain for water changes, I've always just siphoned water out... choking on nasty saltwater sometimes... talk about gross....
 
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