here is what I have done so far:





that is my plan, and the styrofoam was purchased, just hasn't been carved yet.

[quote name='NVCichlids' date='Jun 23 2008, 10:23 AM' post='40169']
here is what I have done so far:





that is my plan, and the styrofoam was purchased, just hasn't been carved yet.
[/quote

wow! thats great so far....
what size PVC is that? I bought 1/2" is that too small?

It'll never work! You're DOOMED!!

here is what I have done so far:

that is my plan, and the styrofoam was purchased, just hasn't been carved yet.

I did a river manifold in a 33L last year, it didn't work super for me but I'm about to try it again.

Thought #1:

The "return" needs to handle the same volume of water as the pump is pushing out the other end. You have only a "one-holer" .... the suction will be fierce. I'd suggest 2 return holes per pump, or make the entire manifold larger diameter than the neck to the powerhead. Or ...

I found some approx 6x3" cylindrical "pre-filters" at the garden pond section of my local Home Depot that slid neatly over 1" PVC. I happened to have some pre-perforated "swiss-cheese" pipe of the same diameter (I'd swear I got it from JehmCo but I'm not finding it there now), so I cut off a couple of 7" pieces, put them in the PVC up-pointing T's, slipped on the pre-filters, and added std PVC caps on the top .... so I essentially had 12 linear inches of slower rate, safe for fish sponge intakes. Because of the diameter of these prefilters, the manifold had to be about 4" in from the short edge of the tank, not full-length as your picture shows. Not the prettiest setup with the "Twin Towers", but effective.

Using two Mag-# pumps, the water movement part of this worked great.

But in my garage in Florida, even with some A/C I couldn't keep the water temps down enough for the darters I wanted to keep. (Summer power failures where my gear didn't automatically turn back on was a big factor, I have an hefty UPS for my fishroom air pump but it won't handle the window A/C.) Next version will be indoors where the ambient temp is better regulated. And I may move the pumps out of the tank entirely.


Thought #2: By chance yesterday I was googling around and ran across a new term to me, "gyre" tanks as a way of getting unidirectional velocity. In short, put a full height divider down the middle 80 or 90% of the tank, and trick the water into doing a race-course pattern. In one example I saw, the divider was horizontal like a shelf, and the water was doing an oblong hamster wheel thing. That was for corals, but maybe some kind of "open-ended plenum" variant would work for fish. A vertical divider for fish would be more conventional, but I'm guessing it'd work best on a wider-than-normal tank,

Part of the argument for this approach is that a whole tank of rotating water has a lot of momentum, and the pump's outflow is used to keep accelerating the water, rather than fighting the bounce-back of its own return. (If that makes any sense.)

Interesting to think about.

I did a river manifold in a 33L last year, it didn't work super for me but I'm about to try it again.

Thought #1:

The "return" needs to handle the same volume of water as the pump is pushing out the other end. You have only a "one-holer" .... the suction will be fierce. I'd suggest 2 return holes per pump, or make the entire manifold larger diameter than the neck to the powerhead. Or ...

I found some approx 6x3" cylindrical "pre-filters" at the garden pond section of my local Home Depot that slid neatly over 1" PVC. I happened to have some pre-perforated "swiss-cheese" pipe of the same diameter (I'd swear I got it from JehmCo but I'm not finding it there now), so I cut off a couple of 7" pieces, put them in the PVC up-pointing T's, slipped on the pre-filters, and added std PVC caps on the top .... so I essentially had 12 linear inches of slower rate, safe for fish sponge intakes. Because of the diameter of these prefilters, the manifold had to be about 4" in from the short edge of the tank, not full-length as your picture shows. Not the prettiest setup with the "Twin Towers", but effective.

Using two Mag-# pumps, the water movement part of this worked great.

But in my garage in Florida, even with some A/C I couldn't keep the water temps down enough for the darters I wanted to keep. (Summer power failures where my gear didn't automatically turn back on was a big factor, I have an hefty UPS for my fishroom air pump but it won't handle the window A/C.) Next version will be indoors where the ambient temp is better regulated. And I may move the pumps out of the tank entirely.
Thought #2: By chance yesterday I was googling around and ran across a new term to me, "gyre" tanks as a way of getting unidirectional velocity. In short, put a full height divider down the middle 80 or 90% of the tank, and trick the water into doing a race-course pattern. In one example I saw, the divider was horizontal like a shelf, and the water was doing an oblong hamster wheel thing. That was for corals, but maybe some kind of "open-ended plenum" variant would work for fish. A vertical divider for fish would be more conventional, but I'm guessing it'd work best on a wider-than-normal tank,

Part of the argument for this approach is that a whole tank of rotating water has a lot of momentum, and the pump's outflow is used to keep accelerating the water, rather than fighting the bounce-back of its own return. (If that makes any sense.)

Interesting to think about.

NVChiclids, you have the same setup as me.... I hope we can both learn from this...

what about 2 returns using 1/2 inch pipe and a 110gph pump?

Edited by DooSPX, 24 June 2008 - 09:36 AM.

I filled the tank up to make sure it holds water with the setup I have in and it ran fine. The water was circulating with ease and there were no visible flaws in the system. Now over time there may be problems, but from what I saw in the 20 minutes it was running, all was fine.

Now the downfall I have is deciding if I want to complete this tank or switch over and do another planted "amazon" or "swamp" tank.

I filled the tank up to make sure it holds water with the setup I have in and it ran fine. The water was circulating with ease and there were no visible flaws in the system. Now over time there may be problems, but from what I saw in the 20 minutes it was running, all was fine.

Now the downfall I have is deciding if I want to complete this tank or switch over and do another planted "amazon" or "swamp" tank.

thats great news, glad to hear that your setup is working. I have a couple questions for you though if you dont mind. What size pipe is that? Also, what size powerhead is that?

thanks so much!!!
Good luck with the tank!!!

answered in a PM, but for others who care the powerhead came from a 55gallon tank, but for the gallons/hour I am not sure and the pipe is 1/2".

the only thing that I did was turn the end piece down and it will be forced to "bounce" off of a few rocks, but like I said before, i might just be turned to having this tank turn into a amazon river biotope or another slackwater biotope, I am not sure yet.

answered in a PM, but for others who care the powerhead came from a 55gallon tank, but for the gallons/hour I am not sure and the pipe is 1/2".

the only thing that I did was turn the end piece down and it will be forced to "bounce" off of a few rocks, but like I said before, i might just be turned to having this tank turn into a amazon river biotope or another slackwater biotope, I am not sure yet.

thank you, I received your PM. How strong of current does that system make??
I only need 2-3 mph current... I am thinking of a powerhead made for a 30....

thank you, I received your PM. How strong of current does that system make??
I only need 2-3 mph current... I am thinking of a powerhead made for a 30....

Lets just say it is more of a rapids tank than a river.

Lets just say it is more of a rapids tank than a river.

how strong do you think it will be with a 20G or 10G powerhead?

how strong do you think it will be with a 20G or 10G powerhead?

Honestly I do not know because this powerhead that I have is the only one I have ever owned.