I'm going to make one of these.

http://www.loaches.com/articles/river-t ... old-design

Has anyone else made something similar and how did you like it?

Cheers

Tis a neat idea. What sort of fish are you going to put in the tank?

I was thinking of trying it for my native torrentfish, but in the end was lazy and cheap, and just put two kickass (3500lt/hr each) at one end of the tank disguised under a pile of rocks.

However I did have bit of a chat with the guy who wrote the article about amount of flow needed.

He recommended a *minimum* flow of 16 x total tank volume per hour.

(so if you have a 10 litre tank you want a 160lt/hr pump or combined output.

However I could see for my fish 16x would have been way too low. These fish would sit 1cm from the outlet of a 300lt/hr pump) so I just went with the strongest I could get.

With the 7000lt/hr combined flow I definitely have some awesome current in there and the fish are *quite* relaxed about it. I am sure it could be stronger! I have the outlets of the pumps aimed across this large flat rock. Frequently the torries will sit on the rock facing the outlets simply VIBRATING in the current before they relax and go WEEEEEEE backwards! Fun to watch but I suspect it is more fun to do.

To see my torrentfish moving about in the current of my riffle tank:

The only problem I have is the pumps crank up the temperature drastically. My fish need *cold* water. Not a worry if doing tropicals of course.

If you keep fast-current fish I STRONGLY recommend doing a fast-current aquarium. It will really change the behaviours and *make sense* of the shape of the fish.

(oh remember that your external filter flow won't count into the equation as strongly as the lt/hr label on it says. That is the flow if there is no 'head' (vertical height) on the pipes. It goes down dramatically the further the filter is below your tank)

Keep us updated on your project!

Thanks for the info. Great video too.

I was thinking of perhaps doing this to a couple of smaller 100L ish species tanks to keep the powerhead size down.

I'm definitely going to set one up for hillstream loaches and I would like to do a more tropical tank as well. But haven't decided on species yet.

Any suggestions?

That is the flow if there is no 'head' (vertical height) on the pipes. It goes down dramatically the further the filter is below your tank)

Keep us updated on your project!

Head is not vertical height of the pipes. Head is the difference in height between the water inlet water(The water height of the tank) and the outlet, basically how far the filter has to lift the water above the height of the water source.

If your filter's outlet is a couple inches above the water then you have a couple inches head. If it's at the surface or below you have no head.

From aquariumpros.com

"Head pressure" on the other hand is more complicated. "Head" may be simply defined as any resistance to the flow of a pump. When pump manufacturers list the head pressure, they are referring to the vertical discharge pressure head. Described in very simple terms, a pump's vertical discharge "pressure-head" is the vertical lift in height (usually measured in feet of water) at which a pump can no longer exert enough pressure to move water. At this point, the pump may be said to have reached its "shut-off" head pressure. When you look at a flow curve chart for a pump, the "shut-off head" is the point on the graph where the curved line becomes horizontal as the flow rate at that point is zero. The higher a pump's head pressure, the more powerful the pump

All pumps have 3 major variables.

Lift, head and pressure.

Lift: how high will a pump lift water from below itself. Most aquarium pumps do not need to worry about this as they are nearly always below the surface of the water. Internal of external, gravity does the job.

Head: How high the pump will push water above itself.

Pressure. The higher the head the less the pressure.

I forgot flow rate or litres per hour.

Obviously the lower the pressure the lower the L.P.H.

The head you're referring to is the pumps maximum head. Maximum Head is NOT how high the pump will push water above itself, it's how high above the surface of its water source it will pump.

If you have a pump with a max head of 10 feet pumping water from a water tank with a water level 20 feet above it and on the outlet is an open vertical pipe, the height the water on the outlet side will reach will be 10 feet higher than the height of the water tank, or 30 feet above the pump.

Agreed!! But the higher the head, the less the pressure, hence less the flow

That is the flow if there is no 'head' (vertical height) on the pipes. It goes down dramatically the further the filter is below your tank)

What is actually being talked about here is friction, from the pipe, bends, etc. It is measured in head height because it is a convenient and easy way to think about it.

but anyway... back to the manifold design....

Bugger Bugger. Can't sleep.

Got up for a cuppa and a fag.

L144 have just spawned for the first time (yeah)

I agree with Stella.

Ira perhaps you could give me the benefit of your infinite wisdom and discuss this manifold design and we could start a new thread re: pump head.

In a design like that the only thing that would realy matter would be "friction loss" which is the loss of head caused by friction of the water moving through the system (including the resistance to the flow caused by the sponges on the inlets and the friction of the water moving through the pipes and pumps. The larger the pipe diameter, the less friction loss in the pipes. There is no head as the water level is the same above the inlet as it is above the outlet.

Why not just use the wave making pumps used in reefing? Tunze, Seio etc

They would work but are expensive options, even the small uncontrolled tunze streams cost into the hundreds. Plus the flow for reefs tend to be more random chaotic, where a steam bio-type wants linear flow.

One good option would be a gyre which give really good flow using smaller pumps

http://www.advancedaquarist.com/2007/1/aafeature#h5

And while I'm posting links here is one to a calculator for head loss (height), its interesting when you see how much difference 1 elbow makes.

http://www.advancedaquarist.com/2007/5/aafeature2

Why not just use the wave making pumps used in reefing? Tunze, Seio etc

I recon making a manifold system would be far cheaper and also double as a filter

You mean...A closed loop. Also used heavily in marine tanks. No reason a handful of seios or similar couldn't be used, I think. You can get the whole tank swirling in a pretty laminar fashion with a couple.

A couple of these might be good.

What do ya recon?

http://www.marineandreef.com/Rio_Seio_P ... i00862.htm

I decided to make a smaller version for my first attempt.

I also decided to use poly pipe instead of pvc to keep the cost down.

I started with this:

Pipes and fittings $15 and a beer just coz

BY the time the beer was finished

Intakes and sponges added

After another beer the power heads were fitted.

2 x 300lph at $12 each from the auction site.

The wine is my wifes I promise.

Fitted into the tank

Gravel, Rocks, Wood and Water added

The tank has approw 50L in it.

With 2 x 300lph power heads I am pumping the volume of the tank 12 times per hour.

There is some backwash off the intake wall but it helps to create some nice eddies and current variations.

Total cost $39

Does that cost inc the 2 double browns? hahaha

I think purplecatfish looked at this option for his river tank for the Sewellia lineolata loaches he has.

I'd think you'd want a lot more than 600LPH if you're wanting to replicate a river?

It Depends on the river that you are trying to replicate.

This is just version 1

I think purplecatfish looked at this option for his river tank for the Sewellia lineolata loaches he has.

I have 3 sewellia lineolata and 5 Beaufortia kweichowensis that i am planning to put in this tank

Wow, this is awesome. I think I might make something similar...I just need a tank to put it in now!!