DIY River/Riffle Tank flow.

Chris_A

Large Fish
Oct 14, 2008
615
0
0
Edmonton, Alberta, Canada
#1
So long story short, I've wanted to do a high-flow tank for quite some time but never bit the bullet and did it. I guess the reason is even though I know it's OK I've never been comfortable with the intakes on the manifolds I've seen online. I truly do want to reduce the possible eddies on the end glass by the intakes. SOooo, I think I finally have some ideas.

1) I have an old Little Giant 3MDQX-SC sitting around doing nothing and I think using it as a closed loop would work best. No difference you say, here's the difference ;). I recently had black Cor-x (corrigated plastic sheets) become available to me, a 4x8 sheet for a 6 pack of beer... good price IMO lol. So what I'm thinking of doing is piercing 1/4" holes on 3/4" centers covering the whole surface. Then put one of these sheets on both ends of a 22 gal with the intake and outlet manifolds behind them. The hope is that it will add an extra level of diffusion to the current and suction.

2) The other thing I was thinking of instead is inspired by an artical I read about a Tsunami "Cloak" researchers are trying to develop. It would basically be teardrop shaped rods vertically on each end with the points facing in the direction of the flow. With enough rows of rods (say 3 minimum?) you can "hide" the end of the tank but still allow free flow of water around the rods. Again, the theory is all about diffusion.

For anyone who's made it this far ;) here's the question. What do you think would be more effective? Looking for anything here questions, comments, ideas, gut feelings, remarks on me being insane... whatever :). The only thing I'm TRULY looking for is actual linear flow, after that... everything is fair game.

Chris
 

Lotus

Ultimate Fish
Moderator
Aug 26, 2003
15,115
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Southern California
home.earthlink.net
#2
You've probably already seen this article on river tanks: A River Runs Through It — Loaches Online

We went the simple route on our loach tank. It's 72" long, and we wanted flow. After trying several powerheads, we ended up using a Koralia #4 powerhead. We've had problems in the past with traditional powerheads with fish getting caught in them, or if using a sponge, it gets dirty fast.

Whatever you decide on, make sure that the intake areas are well covered so that fish can't get into them.
 

Chris_A

Large Fish
Oct 14, 2008
615
0
0
Edmonton, Alberta, Canada
#3
lol, yeah actually I posted that exact link earlier today :). Thanks though.

I had thought about the stream powerheads, and absolutely they work, but I'm hopeing for more single direction flow (rather than having the water break on the opposite glass and recirculate back). Actually, I have an Eco-mod for a MJ 1200 that got me thinking about all this again.

So far as intake strainers, with the 1100GPH (0' head) do you think 3 2" pipes with 5/64 slits every half inch standing vertically (approx 13" tall) would be sufficient? I'll probably have to mill them with a slitting saw to make them look professional.

I think I'm going to have to machine a hub for the outlet manifold I want. Was thinking 6, maybe 7 1" outlets (for 183 or 157GPH each) in a hexagon shape but that really depends on what I can find for solid PVC blanks at work. Still haven't desided if I want to drill the tank for those outlets or have the manifold internal... Hmmm. I'm kinda thinking drilling that many holes in one pane is asking for it to crack.

Either way, I know I'm kinda going to the extreme here but I like "unique" ;).

Chris
 

Lotus

Ultimate Fish
Moderator
Aug 26, 2003
15,115
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Southern California
home.earthlink.net
#4
I think it would considerably weaken the glass to have multiple drill holes. Probably better to have a single hole, and then have the manifold inside the tank.

To really recreate a stream, you'll want stronger flow in the center and less on the sides. The fish will prefer some areas of lower flow in which to rest.
 

Chris_A

Large Fish
Oct 14, 2008
615
0
0
Edmonton, Alberta, Canada
#5
To really recreate a stream, you'll want stronger flow in the center and less on the sides. The fish will prefer some areas of lower flow in which to rest.
I was originally thinking that with the diffused flow and use of decorations slow spots wouldn't be an issue... but I see your point. Maybe if I use the divider method (option 1 in the first post) I could reduce the hole size, or even not make them, in some spots on the the back wall and/or the back corner.

So what do you have stocked in your 72" tanks?

Thanks!
Chris
 

Chris_A

Large Fish
Oct 14, 2008
615
0
0
Edmonton, Alberta, Canada
#7
Mostly I just want to move some fish I already have. Dawn Tetra's and Clown Plec's. I've always wanted to try some of the smaller Hillstream loaches but I've never had the tank to do it on the odd occasion I find some. there's one LFS that gets a variety in semi-regularly. Seen Sewellia lineolata, Gastromyzon scitulus and at least 2 species of the thin bodied types (I don't remember what they specificly looked like for ID). Who knows, maybe I'll add some White Clouds eventually... I LOVE the colours on them ;).

Oh, if I do find some Hillstreams the P. maccus will be back into the 90 (or another tank) so no worries about possible damage :).

Chris