Closed loop circulation? Why/Why not?
- Thread starter REEFFER MADNESS
- Start date
REEFFER MADNESS
New member
sweet set-up. Thanks for sharing
TheH
New member
I think one of the major advantages of powerheads is the ability to change/upgrade/downgrade without too much trouble. Even simply repositioning the flow is tough with closed-loop.
Also, down the line if you decide to sell the tank (upgrade or leave the hobby), it's easier to sell a tank without too many holes in it. Even if the buyer is going for a closed-loop as well, almost no one agrees on just where all the holes should be.
Also, down the line if you decide to sell the tank (upgrade or leave the hobby), it's easier to sell a tank without too many holes in it. Even if the buyer is going for a closed-loop as well, almost no one agrees on just where all the holes should be.
graveyardworm
Premium Member
My CL is all over the top of the tank and completely removeable. With true union valves on both input and output the pump is easily removed with minimal spillage. Locline on the outputs is a must. Really the only downside to the CL IMO is power consumption.
oldsaltman
New member
I have six line lock fittings on the back of my tank running from my CL. I can adjust them where ever I need the flow. I have not seen any downside to my CL. 
I don't think I would build another tank without one.
I don't think I would build another tank without one.
zachtos
Active member
Closed loop
pros
no maintenance
more flow w/ less energy if properly designed
less junk in the tank
less heat transferred to the water
cons
if your pump goes down, you have no flow
a leak can be a big problem
harder to install
may not be as quiet as a powerhead setup
I personally have used both and prefer my closed loop. (36,000gph surges max). =)
pros
no maintenance
more flow w/ less energy if properly designed
less junk in the tank
less heat transferred to the water
cons
if your pump goes down, you have no flow
a leak can be a big problem
harder to install
may not be as quiet as a powerhead setup
I personally have used both and prefer my closed loop. (36,000gph surges max). =)
Los
New member
There are some excellent points raised here on both sides. I have a 360 display with 2 closed loops being fed by 2 Oceans Motions and 2 Dart Golds. My tank is a visible on both long sides, so this allows me to get flow throughout the middle of the tank. Even so, my preference is for the Tunzes I'm using as well. Those suckers throw out an immense amount of flow for a fraction of the electricity. I figure they use about 50% of the juice and they produce a bit more flow. The downside is that they are visible, but that doesn't bother me too much. I also have a 90 in which I use 6101s instead of the Tunze 6201s I'm using in the 360. Two of those produce a ridiculous amount of flow in the 90, bordering on too much, and when combined with a Tunze 7095 multi-controller - an absolute must - the chaotic water flow is something to be seen.
The biggest negative with a closed loop like mine is that it required 10 holes in the bottom of the tank, 2 drains and 8 outlets. Connected to each of the holes is plumbing either in the form of a large plastic grated intake filter or the plumbing pieces used to direct the flow inside the tank. That's 10 pieces of plumbing inside the tank and once the holes are drilled, you can't move them. What made this difficult was having to arrange my rock work such that the rocks fit in between all that PVC in the tank while also hiding it. In the end, I managed, but my aquascaping was driven as much by all that plumbing as anything else.
Not to confuse the issue, but I think it's relevant: there's one big bonus to using closed loops which I hadn't expected. Having outputs on the bottom of the tank and pointed upwards is a great way to create flow in such a way that detritus is blown back up into the water column.
Finally, if you do decide to go with a closed-loop, definitely (trust me on this one) contact Paul at Oceans Motions. He is a great guy and he gave me a lot of great advice on how to set up my closed loops - at no charge. His service is awesome.
Hope that helps.
The biggest negative with a closed loop like mine is that it required 10 holes in the bottom of the tank, 2 drains and 8 outlets. Connected to each of the holes is plumbing either in the form of a large plastic grated intake filter or the plumbing pieces used to direct the flow inside the tank. That's 10 pieces of plumbing inside the tank and once the holes are drilled, you can't move them. What made this difficult was having to arrange my rock work such that the rocks fit in between all that PVC in the tank while also hiding it. In the end, I managed, but my aquascaping was driven as much by all that plumbing as anything else.
Not to confuse the issue, but I think it's relevant: there's one big bonus to using closed loops which I hadn't expected. Having outputs on the bottom of the tank and pointed upwards is a great way to create flow in such a way that detritus is blown back up into the water column.
Finally, if you do decide to go with a closed-loop, definitely (trust me on this one) contact Paul at Oceans Motions. He is a great guy and he gave me a lot of great advice on how to set up my closed loops - at no charge. His service is awesome.
Hope that helps.
TulsaReefer
New member
I have a 220G (6 foot long tank) that has a Vortech MP40w on each end. I can move up to about 6400 GPH with this setup if I put both on max flow, though I run them in reef crest at 100% in anti-sync mode so the flow is lower than that but is continually moving back and forth in the tank. Total wattage needed for this is < 48 watts (Vortech is rated for up to 24 watts each at max, since one is running slower all the time the average is probably about 30 watts combined total). I have a couple Tunzes as well, they are modified 6025 nanos doing maybe 1000GPH, each pulling maybe 7 watts. I get great broad flow (really more of a surge) from the Vortechs, didn't have to drill any additional holes (which means I didn't void my 20 year new tank warrantee), and have more than enough flow for my SPS and other corals to be growing so fast I'm getting behind on trimming them back.
I'm not against closed loops by any means, I looked long and hard when I built out this tank, but when I looked at the amount of plumbing I'd need under my cabinet to get the same amount of flow I decided it just wasn't going to happen. Also the idea that I'd void the warrantee on my new tank wasn't something I really liked either. Without the plumbing I have room for a 40 breeder sump, and a 29 gallon fuge, as well as some room to spare. I seriously looked at using a Dart or two with an Oceans Motion, but in the end it just seemed like too much complexity compared to dropping in the pair of Vortechs and being done with it.
And electric cost is not even close, a pair of Gold Darts pull what, 130 watts or so each? So, 260 watts per hour, every hour of every day, and no easy way to even attempt to throttle them back at night (Vortech has a night mode where they run at 50% power). So your consuming roughly 6 KWH per day on pumps alone. At say .12 per KWH, that's about .72 per day, or $21 per month in electric for a closed loop alone. The Vortechs will pull say 40, so about 1 KW per day, so about $3.60 a month at same .12 price per KWH. And since they run at 50% for 10 hours a day during night mode, I doubt they even pull that much in the end.
As for getting detritus up to the water column, turn a pair of Vortechs at 100% in continuous mode (green) for a few minutes and it will definately stir things up. I do this once in a while just to give everything a "storm surge". Sucks things right off the bottom in the undertow that it builds up.
Another benefit I see with Vortech/Tunze is that both can be battery backed up quite easily. This for me is a nice piece of insurance as I live in an area with quite a few storms and power outages.
As for heat, Vortechs motors are on the outside of the tank, so no heat at all in the tank. I have problems in the winter keeping my tank warm, I almost wish I had more excess heat from pumps during the winter.
I'm not against closed loops by any means, I looked long and hard when I built out this tank, but when I looked at the amount of plumbing I'd need under my cabinet to get the same amount of flow I decided it just wasn't going to happen. Also the idea that I'd void the warrantee on my new tank wasn't something I really liked either. Without the plumbing I have room for a 40 breeder sump, and a 29 gallon fuge, as well as some room to spare. I seriously looked at using a Dart or two with an Oceans Motion, but in the end it just seemed like too much complexity compared to dropping in the pair of Vortechs and being done with it.
And electric cost is not even close, a pair of Gold Darts pull what, 130 watts or so each? So, 260 watts per hour, every hour of every day, and no easy way to even attempt to throttle them back at night (Vortech has a night mode where they run at 50% power). So your consuming roughly 6 KWH per day on pumps alone. At say .12 per KWH, that's about .72 per day, or $21 per month in electric for a closed loop alone. The Vortechs will pull say 40, so about 1 KW per day, so about $3.60 a month at same .12 price per KWH. And since they run at 50% for 10 hours a day during night mode, I doubt they even pull that much in the end.
As for getting detritus up to the water column, turn a pair of Vortechs at 100% in continuous mode (green) for a few minutes and it will definately stir things up. I do this once in a while just to give everything a "storm surge". Sucks things right off the bottom in the undertow that it builds up.
Another benefit I see with Vortech/Tunze is that both can be battery backed up quite easily. This for me is a nice piece of insurance as I live in an area with quite a few storms and power outages.
As for heat, Vortechs motors are on the outside of the tank, so no heat at all in the tank. I have problems in the winter keeping my tank warm, I almost wish I had more excess heat from pumps during the winter.
REEFFER MADNESS
New member
Thanks for all the input!
wooden_reefer
New member
Powerheads and the likes are much more energy efficient than a closed loop with plumbing. Over the years the costs can be very different. There is much less friction loss.
Is this not quite true?
Is this not quite true?
zachtos
Active member
No, A well designed closed loop system can be far superior to powerhead based setup. My zachtos storm drive provides around 25,000gph surges (can go to 36,000gph) and I have beautiful random strong flow as it pulses back and forth. My overall energy consumption (averaged between day/night mode) is around 175W (includes a fan to keep motor cool). A similar designed powerhead system would require around 200W and all that heat would be added to the system. I have no maintenance and only one moving part to worry about that can be serviced for less then $100 at any electric motor shop. I also have not needed to turn my air conditioner on yet this year to my house (partly from the removed powerhead heat).
google the device if you want a video.
google the device if you want a video.
wooden_reefer
New member
Isn't 200W a lot of power for powerheads and the likes?
I think most are under 20 Watts each. So 200W would be 10-15 powerheads or the likes.
Isn't this true?
If the pump for the closed circuit is far away, the heat generated will be far away, but the friction loss for the travel is also greater.
I think most are under 20 Watts each. So 200W would be 10-15 powerheads or the likes.
Isn't this true?
If the pump for the closed circuit is far away, the heat generated will be far away, but the friction loss for the travel is also greater.
zachtos
Active member
To replicate my system (25-36,000gph), you will need around 6-8 tunzes at 25W or greater each. Friction loss is pretty much nill. It's closed loop. I use higher pressure to boost the flow through eductors. My system was far cheaper then a comparable powerhead setup, and is saving me money with low heat transfer to the tank, and very very low maintenance costs. I got sick of cleaning power heads or replacing expensive failed units/props.
wooden_reefer
New member
Closed loop has frictional losses thru the plumbing.
There is also losses due to sudden expansion and contraction. In a way, powerheads also has frictional losses due to sudden expansion.
There is also losses due to sudden expansion and contraction. In a way, powerheads also has frictional losses due to sudden expansion.
saltydog1
New member
<a href=showthread.php?s=&postid=14739104#post14739104 target=_blank>Originally posted</a> by 96vette
I'm running a closed loop pump on my 160 cube
consist of an OM 4-way version 3 drum and blueline 70
bulkheads are bottom mounted but with tru-union ball valves maintenance is a cinch.
Excellent job!!
My impression is that most people still want a sump. I have a Hang-On-Tank refugium, and the problems I've had with the overflow have thoroughly convinced me: If I ever have a tank with a sump, the DT will be drilled. If my overflow had lead down to a sump, rather than across to a refugium, my floor would have been wet a half-dozen times by now.
Would I put a strong enough return pump on the closed-loop that I wouldn't need powerheads? I dunno. I might keep a couple of Koralias, just for the spot flow possibilites. What I do know is that based on my experience so far, I don't trust overflows.
Would I put a strong enough return pump on the closed-loop that I wouldn't need powerheads? I dunno. I might keep a couple of Koralias, just for the spot flow possibilites. What I do know is that based on my experience so far, I don't trust overflows.
I would do overflows as your exhaust and then your returns for all your flow. If you properly size your exhaust you can get all of your flow from your returns.
http://www.glass-holes.com/ has some great stuff to help you get plenty of drain to get your return lines a flowin'.
Which means you'll want a sump. I would only use closed loop for increased flow. At some point your tank could be so big that using your return lines only for flow would be a little rediculous but for your size tank I don't think its out of the question.
GL.
http://www.glass-holes.com/ has some great stuff to help you get plenty of drain to get your return lines a flowin'.
Which means you'll want a sump. I would only use closed loop for increased flow. At some point your tank could be so big that using your return lines only for flow would be a little rediculous but for your size tank I don't think its out of the question.
GL.
I think I'm getting confused about terminology.
If I had a sump, and the return flow from the sump was the main source of flow in my tank, would that be considered a Closed Loop?
Or,
If I had a tube that came out of my display tank, went through a pump, and went back into my display tank, with no diversions along the way, existing only to provide flow, would that be the true and proper definition of a Closed Loop?
If I had a sump, and the return flow from the sump was the main source of flow in my tank, would that be considered a Closed Loop?
Or,
If I had a tube that came out of my display tank, went through a pump, and went back into my display tank, with no diversions along the way, existing only to provide flow, would that be the true and proper definition of a Closed Loop?
