If you could - re: circulation

[sphelps]

Both can be good, in general for larger tanks a closed loop can be a cheaper alternative. Here's one I did on a custom 270 gallon:





Pump outputs were placed through the bottom pane and the inputs on the back to avoid sucking in sand. Also I went with two inputs rather than one single to reduce the suction velocity.
I also installed a 4-Way OM and mounted it sideways over the sump for easy maintenance which is key for such a system, you need lots of space otherwise it's just a headache waiting to happen.



The outputs where covered with rock using some zip-ties .






So you do get a clean look with the closed loop, but it will probably use more power than a tunze setup. However a tunze setup is going to cost a little more but if you plan ahead you can generate a clean look this these powerheads as well. I've always liked the idea of making your tank a little wider and building an acrylic curtain in the back and placing the tunzes behind the curtain alowing only the nozzles to penetrate into the visible tank area through strategically placed holes.

A tunze setup will also give you more control and better alternating flow. In my tank I use both, a closed loop to produce the majority of the flow rate and a tunze to provide a short right angled wave and better water alteration.

[levi1803]

WOW, awesome looking setup

[Delphinus]

Are closed loops *really* a cheap alternative? Seems to me when you start getting into the >2000gph range, the DC drive motors (Tunze, Korallia, Vortech, etc. etc. e-i-e-i-o) edge out the inline pumps...

[fkshiu]

One thing about closed-loops that is easy to forget is the cost and complexity of all the extra PVC. All those unions/valves/elbows/etc. can really add up in a significant way.

[sphelps]

Well, I look at it as a cheaper option. To me I see a closed loop using a Dart pump and 4-Way OM costing around $600-700 plus you have to consider plumbing and drilling costs which can make a total around $1000.
You can get a tunze kit with 2 pumps and controller for the same price but the 4 way OM provides 4 points of flow origin where as the tunze kit only 2. So really you need two tunze kits which costs double. So closed loops are GENERALLY cheaper for larger tanks.

Although some would argue you get way more flow from all those tunzes, try running a Dart at zero head next to a tunze and tell me which is greater. In addition the fact that you can use nozzles on a closed loop also creates high velocity streams which travel further and you with multiple nozzles pointed at multiple areas of the tank you eliminate more dead space.

[Delphinus]

Oh, I don't doubt you get wicked flow out of a closed loop using a Dart pump.

But the flip side is, at 0' of head the Dart is pushing out 3600gpm and consuming 180watts to do so.

A single Tunze 6101 is capable of pushing 3000gph and consumes 36w. So you can have 5 Tunzes before you have the same electrical draw as the Dart.

Of course the flip side is that 5 Tunzes will set you back $1500. Unless you find them used or something like that.

But a more realistic setup is maybe 2 or 3. So let's say 3 Tunzes versus 1 Dart.

Dart: $240
OM-4way: Holy crap, $390?? For real? (Based on this page here: http://www.oceansmotions.com/store/p...f071a68a786482 )
180W @ 24hours/day @ $.14/kWh (based on my last month's utility bill once all the extra surcharges and crap are all added in) - $18ish per month

Tunzes: TS24 kit, ... Holy crap again, $1000? Man have the prices on stuff gone up! I paid $800 for mine!!!!
Extra 6101: $435
36W * 3 @ 24 hours/day = $11ish per month

So over a 5 year period (assuming flatline power rates, haha, as if ), total cost of ownership is in the ballpark of:
Dart - $1710
Tunze - $2060

Far out, I just completely deflated my argument. Pop! Psssshhhhhhhhhhhhewwwwwww!! (sound of balloon deflating)

I .. uh, I had no idea the cost on these things had gone up so much. That's just crazy! I think I paid $300 per my two Tunzes (J&L Boxing Day sales one year apart) and $200 for the multicontroller. The current pricing on them is out of this world!

[fkshiu]

Don't forget to add the $300 worth of plumbing/drilling and chiropractor sessions (for the twisting and bending you'll need to do installing all that stuff) to the CL install. This pretty much makes it a wash.

I priced the two options out myself when I was building my tank and went the Tunze route mainly because of the greater flexibility provided by the Multicontroller over the OM - night mode/feed mode/surging/pulsing/etc. versus switching back & forth.

[sphelps]

Originally Posted by Delphinus

Oh, I don't doubt you get wicked flow out of a closed loop using a Dart pump.

But the flip side is, at 0' of head the Dart is pushing out 3600gpm and consuming 180watts to do so.

A single Tunze 6101 is capable of pushing 3000gph and consumes 36w. So you can have 5 Tunzes before you have the same electrical draw as the Dart.

All I know is that power equals pressure times flow so I don't buy tunze's 3000gph rating at 36W. It's kind of like the whole emulator thing which claims to produce 3 times more flow. That's kind of what I meant by put the two side by side and feel the difference.

All things aside, the best is always in combinations. Go with a 4 way closed loop and a tunze wave box and you'll be good.