Under Water Fountain

[nfored]

So here is my idea

Put a small tank in my case a 20 gall with the bottom drilled, inside my larger tank. Place smaller tank on pvc legs, and put a pvc pipe through the bottom of the 20gallon that extends 3/4 the way inside the 20gallon. The put an air line hooked to a pump inside the 20 gallon turn on pump.

Air will build inside the 20Gallon pushing the water level lower until the pvc pipe is no longer submerged thus allowing air to escape until its submerged again. This should always fluctuate and I can't think how to stop that.

Now I put a small pump such as a rio 1700 under the 20 gallon and turn it on. This will shoot water up and make a water fountain, since the top 3/4 is only air.

I think the weight of the tank plus the weight of the water in the bottom 1/4 should hold the tank under water.

Heres a pic

 

[pppp]

Why not use a u shape pipe with a smaller u at one end instead of drilling the tank and pass it through the gap? Drilling it will make the tank weaker.

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How will you hold the tank down? There will be a force of 15g of air, that's almost 125 lb. of lift which is much more than the weight of your 20g tank, I think.

 

[ikevi]

I think the weight of the tank plus the weight of the water in the bottom 1/4 should hold the tank under water.

Sorry but as stated this is completely incorrect thinking. Try holding a 1 gallon jug with 1/4 water and 3/4 air under some water. Now multiply that by 20. That is the force you are going to have to hold down somehow.

 

[nfored]

Hum, yes the tank is no where near that much, I already had it, its pre drilled I bough two of them from a pet store for 20 bucks each.

Well it was a though, I was thinking how cool it would look at night to have a colored fountain light show under water.

This is why I love shared information, I can say my idea and find out how silly it is before wasting precious time on it.

Thanks every one.

 

[tscharf]

why not just take a completely sealed tank, put some water in it, and then put the pump in that, then silicone it to the bottom of your tank? or have the tank upside down like u said and silicone the top edge of the 20 gal to the bottom edge of ur larger tank. have the pump insides with some water and there u go?

 

[Ficious]

or maybe find out how to do this with a good looking fish bowl or something instead of a big boxy 20 gallon.

 

[tscharf]

fish bowl would look cool, you could get the fountain to spray up against the bottom of the fish bowl (which would actually be the top when in the tank) and the water would run down the sides. you could even put LED's around the rim of the fish bowl to light the water as it comes down

 

[Brian G]

would you have to replace the water in the completely sealed tank or fish bowl, if so how would you do that without having to replace the silicone every time?

 

[dmopar74]

google sand waterfall

 

[houie925]

Wouldn't be totally underwater but the best way I see to do this is to use a smaller tank(I would just do four sides with new glass) that is a little taller than the main tank waterline and seal that to the bottom leaving the top open. You could then put the fountain in the smaller tank.