[bell]

i'm moving into a new house in about a week or so, i chose this house due to the vast amount of space for my fish and the 2 car garage.
don't have actual measurments but the finished basement where my oscars will be is about30ftx15ft and i'm thinking of building a tank to simulate a slow "river", meaning current in one dirrection.
my thoughts are 24"wide/20"tall/24ft long, it would be shaped like a u around the perimeter of the room on one end, it'll be plywood with flat glass, i could make the rear wall curved to keep the current smooth, the glass corners would have a 45 degree angle opposite the rear curve.
the big question is how big of a pump to create this slow current? jets could be placed throughout to keep it moving, have the overflow on one end and the return on the other......should work right?
best guess is about 500-600 gallons.

your thoughts?

 

[ishguy]

jets could be placed throughout to keep it moving

Not necessary. Water in at one end out at the other. The water will have no choice but to move.

 

[j rice]

wow that's sounds like a cool idea. but like ishguy said if it were built out of level you would not have to worry about it.
but on the end of your simulated river you would need some sort of simulated lake for the water to go and be pumped to the other end.
the only thing that would bother me is a power failure. so you would have to figure out a place for all that extra water to go in case a power failure would happen. I guess either a real big lake or some sort of overflow.

don't give up on this we can make this happen. :thumb:
just wait till the fish guy reads this. He will be wet

 

[imusuallyuseless]

but like ishguy said if it were built out of level

I dont think thats what ishguy was saying :? Just that if water was being pumped into one end and out the other, it would naturally move the path of least resistance, which would be back to where it gets sucked in. At least i think thats what he's saying :?

 

[Stoolpie]

It's a very cool idea. A quick calculation shows that if you want the water to move about 1" (linear) per second - a reasonable pace - you would need to pump about... 7,200 gallons per hour (2 gallons per second)! This would be about 12 turnovers per hour for the ~600 gallons - very good filtration. That's some serious pumping! If you're capable of building such a tank, though, you're also capable of setting up the plumbing. Good luck!

 

[j rice]

:lol: now that I read it again I think you are right.
oh well, not the first mistake and surely not the last!

 

[Stoolpie]

Just because I was curious, I checked out some water pumps to see what would cover your needs and how much it would cost.
For instance, this pump can get the job done for $250-400 (page is a little slow to open):
http://www.pondmarket.com/store/ind...=53285bc-bd17b89f-785d-466e-aad4-92caace513bd
And a couple of links to other sites:
http://www.pondsandpets.com/servlet/the-59/Pondmaster-5000-gph-Koi/Detail
http://www.pondarama.com/Merchant2/merchant.mv?store_code=POWGS&screen=PROD&product_code=150014
These last two are ONLY 5000 GPH, though (gotta get 2!).
I'm sure some of the DIY pros around here have tips for what to get and where to get it. Of course, any filtration that's done "in-line" will restrict the flow some, so you'll have take that into account.

 

[imusuallyuseless]

7,200 gallons per hour seems a bit excessive, but then again what do i know. But i am curious as to what your formula is so i can better understand???

 

[Stoolpie]

Think of the tank as a long, rectangular tube with a 20"x24" cross section. Now take 1" of length along the tube, so you have 1x20x24". The volume of this is about 2 gallons (use the aquarium calculator in the library). So, you need to pump about 2 gallons per second to have the water move about 1" per second. 2 gallons per second x 60 secs per minute x 60 mins per hour = 7200 gallons per hour. The volume of the tank (by the calculator) is 20"x24"x288"=~600 gallons. Good filtration requires a minimum of 6x tank volume flow per hour - 10x is better. The tank would need at least 3600 GPH for filtration, but then the "velocity" down the "tube" would only be 0.5" per second. Try moving your finger along your desk at that pace - it's a pretty slow moving "river".

 

[illy-d]

The tank would need at least 3600 GPH for filtration, but then the "velocity" down the "tube" would only be 0.5" per second. Try moving your finger along your desk at that pace - it's a pretty slow moving "river".

That's equal to 0.04572 km/hour, or 45.72 meters/hour...

And for the Americans;

0.5 inch/second = 0.028 409 091 mile/hour

I wonder if building the tank out of grade would be better? It would have to be able accommodate the full vloume of water in the event of a power failure though...

 

[ishguy]

The velocity could be adjusted by objects in the water's path just like happens in nature. The same volume of water can be both a slow plodding river and rapids. this might be very desirable. If a rock, for example, obstructs 30% of the flow in one section (I'll let someone else do the math but...) that water will have to move considerably faster around that rock to keep a constant volume. It could be pretty cool!

The "lake" could simply be a sump setup with a regular overflow. Power off would not be a problem.

I have heard of a tank like this at our Ontario Ministry of Natural Resources office here in Toronto. I will see what I can find out...

 

[lomax]

these pumps are better the cimmeron is what i use, two would give you the needed flow rates and a backup min flow if one fails.

http://www.azponds.com/new%20sequence.htm

you need to make reating areas also so the fish do not get all bunched up at the out flow.

 

[illy-d]

YES - Lots of logs, roots and boulders to create currents and back eddies would be awesome! You would probably get to see some interesting behaviour that we of the all glass rectangles don't usually get to experiance!

Have deep spots and shallow spots, places that are sunny, places that are shady!

This could turn out to be an amazing project! - Something that I will be watching closely - and considering for myself if I ever have the space to accomodate it!

Here's a question; The overall length of the tank helps determine the total volume, but does the length of the tank have a corresponding effect on the overall pressure created by the water? i.e. Will the thickness of the glass be a major consideration for this project?

Not really knowing the physics behind it I would naturally think that the depth of water, or height of the tank, would have a greater effect on the pressure exerted on the glass...

 

[bell]

good info guys
i can go narrower, say 18" which is the base of a 75, this would help with the flow, also if i do something this big i will be using concrete to create the entire floor/back wall, this will allow for crative hiding spots along with increasing flow in some areas with a single large pump, i still want jets though so keep things from settling.
i'll get intoi more details when i get home from work
thanks

 

[ishguy]

i still want jets though so keep things from settling.

I think what both lily-d and I are both saying is the excitement will be in the different environments being created. This, although I understand your concerns, includes these, relatively, still areas. Fish often live in these back eddys.

 

[chefkeith]

I've been planning a U shaped river/pond for a few years. Right now, I have my tanks in U formation in my fishroom. The tanks are connected with water-bridges.

For the new river tank, I'd build the entire tank out of Acrylic. My plan is to build it in sections so that the the tank can be moved, if I move.

In essence, I'd be building 6 - 140g tanks that each are 6'x24"x19" and then fitting them together. Each tank would have matching holes routed out of the sides and the tanks would be bolted together.

I could build each 140g tank for about $220. Total cost for 6 acrylic tanks would be $1320 and total volume would be 840g's. Also, I could always add/subtract on more tank sections depending on how much room I have.

I wouldn't want all the sections to have high water flow like a river. I'd want the end section to be planted, this would give the fish a place to breed, and to act as a veggy filter. Another section would be filled with slate caves giving the fish a place to rest.

I'm not sure yet about Filteration. Right now I'm thinking maybe an H-shaped tank would be cooler.

 

[bell]

alrighty here is where i'm at, i was at the house tonite finishing up some paperwork i checked the space again.....a little narrower than i first thought.....about 12ft x12ft is the area for this tank.

thinking about the flow today at work.....the middle section would be a good spot for some creativity, leaving the 2 sides for slower movement, i won't have this tank planted as my oscars will dig everything up and kill them.
acrylic is not going to work for me, i'll be using plywood/glass so i can bend the rear wall at the corners, and the concrete will allow a good barrier and a consistant look.
the basic shape will be made first then epoxied, then i will build the terrain using concrete over aquarium safe expandable foam, plexi, whatever else i'll need.
then the glass wil be installed, not sure how thick i'll need, i'd like to keep the glass/windows about 20" tall.
the filtration system would be below the begining of the "river", the overflow will be a seperate chamber at the end of the "river", this way i can pull water into from the middle/bottom, i think 2 3"pvc tubes would work well for the main returns, a little overkill but will have massive flow capacity should i beef it up in the future.
the sump system will wood also, it will have the typical filtration stages then dump into a very large capacity sump tank with a well for the pump, this will allow the pumps to stay submersed should the water level drop.
having the return pumps as close to the input to the "river" will let the pumps be as efficiant as possible.
too keep from having cold spots near the end of the "river" there will be multiple heaters both in the sump and towards the end of the tank.
this is where i'm at......this is going to happen just a matter of how fast

 

[Stoolpie]

illy-d - length of the tank has no effect on pressure.

chefkeith - looks like you've got a plan, too - very creative thinking!

bell - are you married? If so, I'm sorry to hear about your marriage! :lol: My wife would kill me! This project is pretty massive. Best of luck to you. By the way, with the kind of water movement you're going to have, heaters will probably only be needed in one spot

 

[imusuallyuseless]

illy-d - length of the tank has no effect on pressure.

Just curious why i've read warnings about building a tank over 8'???

 

[Stoolpie]

Can't say for sure about that, but maybe has to do with the stresses that develop with a single piece of glass that big - they have to be secured very carefully. For this project it sounds like there will be a series of "windows" along the length of the tank, so eliminating the stress factor and also keeping the cost contained. Big glass = big $$$.