Fish Tanks Are Hard to Clean…

…but this one must have been an absolute nightmare. Hope they had lots of sucker fish.

This fabulous fish tank was once a main attraction at the Liquid Potion Lounge, a long defunct coffee bar in Evanston, IL (my sort of current hometown). As the pictures attest, the fish did actually use the bridges/tunnels (I wonder which is the more appropriate word here) between the various tanks, but how much so is unclear. Benny and I have long wondered why aquarium manufacturers never tried to develop more interesting tanks and start a craze like Habitrail did with its iconic yellow gerbil tubing. For the armchair physicists in our audience, our original explanation for why the water stays in the tubes despite being at a higher elevation was totally incorrect. See Greg Morrow’s explanation in the comments below. Via Gizmodo

more pics below the fold…

1. #1 Greg Morrow
January 24, 2008

As an actual physicist, I can say that the way to get water up into the tubes is to make them airtight and then pump the air out so that there’s a vacuum. Then atmosphere pressure at the tanks pushes water up into the vacuum.

Air pressure acting against vacuum can raise water 30 feet or so, as I recall, more than enough to fill the tubes shown here.

It actually doesn’t matter at all how deep into the tank the inlet pipe is put, actually; the only thing that matters is the height at which the water is exposed to air.

(You could also seal the tank and open the tube at the top; harder to do, but you don’t have to re-evacuate the tube if bubbles get trapped up at the top.)

2. #2 Nick Van Der Horst
January 24, 2008

Think of it like a giant siphon. All that matters is that the tanks are at the same elevation. If you raised one tank above the other, then the water would flow from the high tank to the lower tank.

3. #3 Dave X
January 24, 2008

As an engineer, I can say that the tube is just a big siphon, and I agree with the physicist. Normal air pressure is 14.7psi or 101300 pascals, enough to hold up 10.3 meters of water under a vacuum.

4. #4 Aquarium Owner
January 24, 2008

As an aquarium owner, I can say that if you put more than 5 or 6 flakes of fish food in there–vacuum or no vacuum–the fish are completely fucked.

5. #5 Dave Briggs
January 24, 2008

Whatever the physical explanation as to why it works, I think it is really cool. Sitting in your easy chair without even having to wear a scuba tank and watching the fish swim above your head! LOL!
Dave Briggs :~)

6. #6 Raging Wombat
January 24, 2008

I’ve often fantasized about having an elaborate aquarium like this, but the prospect of trying to keep it mulm free (all those plexi-glass bottoms!) is so daunting.

7. #7 David
January 25, 2008

So how did they really clean it?

Also i’ve lived in Chicago for years and have never heard of this, where was this cafe located?

8. #8 Jenbug
January 25, 2008

Wow, that is an awesome idea. Makes me think of that Far Side cartoon with the Rhino-trail in the guy’s house.

Think the fish encounter others going the opposite direction and get all uppity commuters? ‘WRONG WAY you fool! GAWD I hate tourists.’

9. #9 Chet
January 25, 2008

From looking at the pictures it looks like there are UV sterilization lamps on the angled upward duct at each end of the tube. These would explain how and why there is no algae growth within the tube itself.

10. #10 neon
April 27, 2009

we you raised one tank above the other, a then the water would flow from the high tank to the lower tank.

11. #11 kayla
November 7, 2009

OMG that fish tank is soooooo cool i wish i had one just like it!!!!!!!!!!!!!!

12. #12 Queen Fricke
July 1, 2012

kutta futta
mutta lutta
=======go gReEn

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July 5, 2012

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14. #14 New Beginning 2012
July 5, 2012

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July 6, 2012

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