Closed Loop Design & Pictures

rlpardue

Member
Hi everyone,

I'd like to solicit some advice regarding a Closed Loop I want to integrate into my 150g 5x2x2 build. Pictures of the tank are attached.

I obtained this tank secondhand with the two 3/4 inch holes already in the bottom. I just got a holesaw from gl*******s that should work with a 1.5inch bulkhead. I plan on drilling two holes for 1.5inch bulkheads in the back panel of the tank, but I don't know where to drill 'em!

I imagine too low and sand would get sucked in, and too high would let air in. I have strainers that should fit the 1.5inch bulkheads.

The pump I will use with this system is a Reeflo Dart (3600GPH) and I'm trolling through used equipment forums looking for an OM 4-way. I plan on having the four outputs coming from the OM:
#1-will go to the two 3/4inch lockline outputs through the bottom of the tank
#2, 3, and 4: will go over the top of the tank because I don't like drilling glass more than necessary.

Alternatively, I could run PVC along the bottom of the tank, from the two 3/4 inch ouputs up to the front of the tank then have them directed toward the top rear of the tank. (If that makes sense).

Anybody see any fatal flaws in my design?

NOTE-I can't figure out a way to shrink the pic's filesize down to meet RC's requirements - anyone know how to do this?
 
Pic

Pic

I've hopefully attached a picture of the bottom of the tank which shows all the drilling that's been done thus far. There's 2x 1" holes and 1x 3/4 inch hole in the overflow, and two 3/4-inch holes in the bottom of the tank.
 
Reducing to 3/4" or 1" anywhere in the return from a Dart is a fatal flow: Friction loss. Using an OM-4 way is a fatal mistake: Friction loss. Sure friction loss is all you deal with in a closed loop, (no static lift,) but still. Also closed loops are static. If the circulation is not right, you are stuck with it, and STILL have to add power heads. You would be better off just using power heads, and avoid the hassles.

Forgetting to put the hyphen in "glass-holes.com" is also a fatal mistake. ;)

Upload the photo to photobucket, then hot link to it. Paste the image location into the "insert image" dialogue box.
 
Uncle so it sounds like you are against CL set ups, is that correct? You signature says 5' wide tank, how do you provide adequate flow to all parts of the tank? How many sides are viewable?
I ask because like I had asked you, I'm looking to upgrade to a tank that is 4' front to back and will be viewable from 3 sides and rimless and I want that clean look
Corey
 
Uncle so it sounds like you are against CL set ups, is that correct? You signature says 5' wide tank, how do you provide adequate flow to all parts of the tank? How many sides are viewable?
I ask because like I had asked you, I'm looking to upgrade to a tank that is 4' front to back and will be viewable from 3 sides and rimless and I want that clean look
Corey
 
LOLOL - it thought I was not saying "gl*******s" and thought I was saying the same word without the "gl" at the front. I thought it had starred it because it was a banned website or something.

Anyway, yes head loss is part of the deal when you use a closed loop. No problem. That's why I went with a Dart rather than a BlowHole (I have GPH to burn). I'll also have a couple of MP 40's on the tank. The reason why I'm going with a CL is because I plan on keeping this SPS reef running for many years and want to be able to adjust the flow as the corals grow out to the point where they would block the flow of MPs.

My CL won't be a "static" one. 3 of the 4 outputs will go over the top and therefore be easy to adjust. Also I plan on having long expensive lockline extensions at the end of those over-the-top outputs.

Does anyone with past experience with closed loop builds see any problems in my plans?

Uncle, thanks for the input BTW. I like to hear anything constructive.
 
LOLOL - it thought I was not saying "gl*******s" and thought I was saying the same word without the "gl" at the front. I thought it had starred it because it was a banned website or something.

Anyway, yes head loss is part of the deal when you use a closed loop. No problem. That's why I went with a Dart rather than a BlowHole (I have GPH to burn). I'll also have a couple of MP 40's on the tank. The reason why I'm going with a CL is because I plan on keeping this SPS reef running for many years and want to be able to adjust the flow as the corals grow out to the point where they would block the flow of MPs.

My CL won't be a "static" one. 3 of the 4 outputs will go over the top and therefore be easy to adjust. Also I plan on having long expensive lockline extensions at the end of those over-the-top outputs.

Does anyone with past experience with closed loop builds see any problems in my plans?

Uncle, thanks for the input BTW. I like to hear anything constructive.

Yes. I have quite a bit of experience with them........
 
LOLOL - it thought I was not saying "gl*******s" and thought I was saying the same word without the "gl" at the front. I thought it had starred it because it was a banned website or something.

Anyway, yes head loss is part of the deal when you use a closed loop. No problem. That's why I went with a Dart rather than a BlowHole (I have GPH to burn). I'll also have a couple of MP 40's on the tank. The reason why I'm going with a CL is because I plan on keeping this SPS reef running for many years and want to be able to adjust the flow as the corals grow out to the point where they would block the flow of MPs.

My CL won't be a "static" one. 3 of the 4 outputs will go over the top and therefore be easy to adjust. Also I plan on having long expensive lockline extensions at the end of those over-the-top outputs.

Does anyone with past experience with closed loop builds see any problems in my plans?

Uncle, thanks for the input BTW. I like to hear anything constructive.

Using a large pump to overcome friction loss, due to improper pipe sizing is a fatal flaw. Just because the water will shoot across the room, doesn't mean you have gallons flowing, just a low volume jet stream--which is a waste of the pump: using much of the pumps capability just to overcome the friction losses. Plumbing design is not a matter of convenience. It is engineering to reduce the friction losses to < 5' equivalent per 100', thus taking advantage of the pumps capability.

Reducing to 3/4", is really out of line. 1" is also. Using loc-line is also very restrictive. Piping of 1.5", all the way into the tank, is reasonable for this pump, and 2" would be far better. It is too bad that the tank in question does not have the facilities to run a performance system; the person that set it up originally didn't know what they were doing--hence my advice to run power heads rather than a close loop: you don't want to make the tank more suitable for a closed loop. Further, since this is to be an SPS tank, we are looking at flow rates ~ 6000 - 9000 gph, minimum--and this closed loop isn't even going to get close, even with the sump return added in.

I noticed you were planning on two 1.5" bulkheads for the intake. I certainly hope you are not planning on 1.5" to the pump intake. The inlet is 2"; a 1.5" intake line will cause it to cavitate.

It was mentioned that I to not care for closed loops. It is not so much that, rather the casual way in which aquarium plumbing is approached, that ends up wasting good pumps, and never gets close to the flow rates that are needed in these systems. I also don't care much for giving advice, and then having the requester "argue" with the response, because it is not what they want to hear. ;)
 
Lots of good issues brought up here.

I'm not sure if I made clear that I'm reducing to multiple 3/4 inch outlets. So, pump's outlet is 1.5", which flows to an OM 4-way, the outlets of which are 1" (unless I can find the 2"/1.5" model used. Then 1" pipe to a Y-splitter, with two 3/4 outputs. (The last section will be replicated 4 times for each of the four outlets of the OM.

On the bulkheads, yes you're right - the plan is definitely to use two of them to spread out the suction pressure. I don't like drilling a massive single hole if I can avoid it. The two 1.5" bulkheads will run to a 2" Tee then 2" pipe will run to the Dart. (which has a 2" intake).

It sounds like you're suggesting that I increase the diameter of the output line from the Dart from 1.5" to 2". That sounds like a good idea, hadn't thought of it. Will doing that improve the flow rates in the segment going from the Dart to the OM 4-way?

Alas, I wasn't the one who said you didn't care for closed loops. Inpt is surely welcome; I will definitely argue with any suggestions but only in an academic and friendly manner, in order to improve system design. I appreciate the input!

EDIT: On a comical but interesting note, the guy I bought the tank from used one of the 3/4" holes on the bottom of the tank as the return line from the sump - he had 23" of lockline running from the hole all the way to the water line at the top of the tank, topping the expensive lockline construction with a diffuser. It was maybe a tad better than going over the top I guess, just an expensive way of doing it.
 
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I can do this with two vortech MP40s, and have ~ 6000 gph worth of water movement in the tank. You are likely to wind up with 1000 gph, and dead spots, if lucky, and not even close to the same character of water movement. :)
 
Add a third or a fourth, and save energy cost, and better performance. LOL.... and not have to deal with that rats nest of plumbing. ;)
 
Uncle I'm only asking if you think there is a "proper way" to establish a CL? Do you feel you have adequate flow on far end of your tank. My next tank hopefully will be viewable by 3 sides and 4' front to back and was looking towards a CL but I am aware of some flaws in a closed loop. For one even using a hammerhead at 6000 gph it's far less than a few tunzes. But just curious as to how effective a few tunzes can be compared to a closed loop to eliminate dead spots.
That's what I was asking in above post
Corey
 
I'd like to take a moment to get back on track with a request for advice in designing a good closed loop. I've already given Vortech enough money lol. I got a Dart for 75$ and an OM for $200.

Goal of the CL is to kick up detritus that settles into nooks in the rock work or behind rocks. Four outlets will blast a portion of the tank, then the MPs will keep said detritus in suspension. My question is not whether I should use a closed loop. I'll take Rich Ross's word for it on that.

The question is: where are the best locations for the outputs of the closed loop?
 
I'd like to take a moment to get back on track with a request for advice in designing a good closed loop. I've already given Vortech enough money lol. I got a Dart for 75$ and an OM for $200.

Goal of the CL is to kick up detritus that settles into nooks in the rock work or behind rocks. Four outlets will blast a portion of the tank, then the MPs will keep said detritus in suspension. My question is not whether I should use a closed loop. I'll take Rich Ross's word for it on that.
In a system with proper circulation, and strong water movement, detritus does not fall out. That is one of the objects of the drill, the others are to carry wastes and CO2 away from the critters, and carry food and O2 to the critters. The cl/power heads also do not replace what is lacking in the overflow/drain/return system. When speaking of SPS flow rates, we are talking 60 - 100x the system volume type flow. You cannot get that with a closed loop--without using a monster pump. With the pressure losses in your proposed closed loop, due to high friction losses (loss of pressure) your closed loop will not be blasting anything.

You are spending a great deal of time, trying to figure out your closed loop, but it is an accessory system. What about your overflow/drain/sump/return system? @ 1500 gph on the return, the corner overflows are going to choke on it. You are going to need a siphon system, and a bit more overflow length. A far more important system to work on.

The question is: where are the best locations for the outputs of the closed loop?

Middle of the water column behind the rocks. At the top of the tank, you are wasting your time. The return pump and overflow keep that water moving. Your Vortechs will keep things moving in front of the rocks.

Who is Rich Ross? As near as I can tell, just another reefer telling people what they want to hear. "A little bit of everything."
 
Uncle, thanks for helping me think through all of this.

The single corner overflow is 12"x6" (quite large!) and contains 2x 1" bulkheads and 1x 3/4 inch bulkhead. I was planning on doing a beananimal overflow since I have three holes already there. Have a Mag 9.5 that I would use with an over-the-top return. Figuring about 800gph for the return seems reasonable; I'd imagine the beananimal would take care of it, no?

The sump is an odd shape, something like 36x20x18. The skimmer is a ReefOctopus I've been using on my 75g, not sure of the model but I believe it was only rated at 150g. I'll have a light bioload so it *ought* to be sufficient. I'll upgrade it later as needed.

If possible, I'd like to avoid purchasing a second MP40 (I only have 1 right now). If a closed loop, coupled with the single MP40 and a couple of 1100-ish Koralias and various stream pumps (hopefully not many, I don't want tank to be cluttered), can provide the flow I need then it would be nice. Budget constraints are very real and overruns would impact my marriage. :)

Do you have a link for any kind of fluid-dynamics-for-reefs information? Calculations of friction loss for elbows, pipe length, etc? I think it would be helpful to familiarize myself with the principles at work then come back with a proposal that's further along (in the right direction).
 
Uncle, thanks for helping me think through all of this.

The single corner overflow is 12"x6" (quite large!) and contains 2x 1" bulkheads and 1x 3/4 inch bulkhead. I was planning on doing a beananimal overflow since I have three holes already there. Have a Mag 9.5 that I would use with an over-the-top return. Figuring about 800gph for the return seems reasonable; I'd imagine the beananimal would take care of it, no?

The sump is an odd shape, something like 36x20x18. The skimmer is a ReefOctopus I've been using on my 75g, not sure of the model but I believe it was only rated at 150g. I'll have a light bioload so it *ought* to be sufficient. I'll upgrade it later as needed.

If possible, I'd like to avoid purchasing a second MP40 (I only have 1 right now). If a closed loop, coupled with the single MP40 and a couple of 1100-ish Koralias and various stream pumps (hopefully not many, I don't want tank to be cluttered), can provide the flow I need then it would be nice. Budget constraints are very real and overruns would impact my marriage. :)

Do you have a link for any kind of fluid-dynamics-for-reefs information? Calculations of friction loss for elbows, pipe length, etc? I think it would be helpful to familiarize myself with the principles at work then come back with a proposal that's further along (in the right direction).
 
Uncle, thanks for helping me think through all of this.

The single corner overflow is 12"x6" (quite large!) and contains 2x 1" bulkheads and 1x 3/4 inch bulkhead. I was planning on doing a beananimal overflow since I have three holes already there. Have a Mag 9.5 that I would use with an over-the-top return. Figuring about 800gph for the return seems reasonable; I'd imagine the beananimal would take care of it, no?

Reasonable flow for this tank would be in the neighborhood of 1500 gph.


The sump is an odd shape, something like 36x20x18. The skimmer is a ReefOctopus I've been using on my 75g, not sure of the model but I believe it was only rated at 150g. I'll have a light bioload so it *ought* to be sufficient. I'll upgrade it later as needed.

That would make the skimmer too small. When considering skimmers that are rated by tank size, the figure needs to multiplied by three. There are no standards for these things, and most are overrated.

If possible, I'd like to avoid purchasing a second MP40 (I only have 1 right now). If a closed loop, coupled with the single MP40 and a couple of 1100-ish Koralias and various stream pumps (hopefully not many, I don't want tank to be cluttered), can provide the flow I need then it would be nice. Budget constraints are very real and overruns would impact my marriage. :)

Well I am not a marriage counselor, ;) so can't help much there. I was given an ultimatum years ago: "The tanks or me!" I said: "FINE!!" My expenses dropped by 75%, so I put up another tank. Not that the tanks were more important, just a way of saying "don't play that game with me." So you don't want my advice on that topic. LOL.

40 - 100x for the system total, 1500 of it for the sump return. As I have said, there are ways around that, but you have to figure that out. :)

Do you have a link for any kind of fluid-dynamics-for-reefs information? Calculations of friction loss for elbows, pipe length, etc? I think it would be helpful to familiarize myself with the principles at work then come back with a proposal that's further along (in the right direction).

There are numerous friction loss charts floating around the internet, generally they will include friction losses for a few common fittings as well. From there it is addition, subtraction, mulitiplication, and division. There is some variation in the numbers with these charts, but we can assume they are close enough.

The charts show the friction loss per 100' of pipe, converted to vertical lift. So the math required is less. Fittings are shown in equivalent feet of straight pipe. Example: You have 5' of static lift. You also have 5' of straight pipe. So that 5' of pipe is evaluated to determine how much extra lift that pipe represents.

There is also velocity head (overcoming inertia) which can easily equate to another foot or so of vertical lift.
 
Hey uncle, do you have experience with using enductors on a CL?

Ive been looking into them a little and My thought would be if you find a high head pump and push through enductors which usually have .300-.375 orifice would using 3/4 plumbing still cut flow too much? If you could get enough pressure to even push 500 gph out of each orifice you could move 2000-2500gph out of each nozzle maybe???
 
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