Backyard Aquaponics
A place to discuss aquaponics

I found this whilst looking for cool fish piccies, it is most interesting, though probably cost prohibitive.
http://www.geekologie.com/2007/03/impossible_fish_tank.php
I do think the idea is cooler than the implementation...they could have done it much nicer, the little hand 'basins' look ugly and added on. A simple split wall with the lower half protruding further than the upper haver would be much better I think, and looked heaps cooler.

yeah agreed, looks tacky

but you gotta admit the possibilities are cool...
Now I just gotta find some1 with a heap of money, and a public place they wish to attract ppl to.

I saw a home fish tank that was a bit that way . . . let me find the link.

Here you go. The bottom of the tank is open, not the top. Water's kept in by virtue of the bottom of the tank is'n't open to air.

Open bottomed fish tank video

The thing that would concern me . . . anyone with a tube or straw could drain the tank down to the level of the holes cut in the side of the tank.

Man, if that vacume pump breaks there's gonna be a mess!!
T.

it could double as a urinal

Yeah we've seen that sort of thing before too... fish loft I think it was called... looks cool huh?
so, the reason that works is by virtue of the top not being open to air, and air not building up inside, allow the water to flow out.
How then does he get away with an airstone in there? surely this would create an air pocket and empty the tank (slowly)

What I don't understand is how they manage to keep enough DO in the water. I thought that if you put water under a vaccuum it tends to degass.

It's not MUCH of a vacuum, and in the video setup, there is an air pump... don't get that. To get 10m of water to stay there, you need -14psi/-100kPa vacuum.
but to get 1m of water to stay there you just need 1.4 PSI or 10 kPa vacuum

But as ElfNori pointed out, there is no need for a vacuum pump. If the top is enclosed, you can make as many pockets like that as you wish without the water coming out. Then all you need to do, is suck the excess air out every now and then...
Still that will result in a vacuum generated by the water of 10kPa/m

RE DO at -10kPa? I have NFI... but I'm guessing it's not that bad.
It's the equivalent of 1000m above sea level.
Do fish live that high?

The air is taken from the top of the tank that's closed. It's just cycling the air back through the water.

RE DO at -10kPa? I have NFI... but I'm guessing it's not that bad.
It's the equivalent of 1000m above sea level.
Do fish live that high?
Think so some of the lakes are pretty high however they have a large surface area for exchange. Glad someone can do the math
Nori
I'd get a bit edgy having something like that, its like a disaster waiting to happen

A crack in the tank is disaster no matter your setup... so the only other way for air to get in there is outgassing.
In which case disaster will be a LONG time building... you'd be able to weather 24 hrs without power I'd expect...
But yeah, it would need maintenance.

I'm a great believer in Murphy's Law KP , and the more complicated things are, the worse it gets.

Anything that needs maintenance can by definition break down. So I agree, complexity is bad for critical systems.
But do you REALLY want to get me started on Murphy's Law, and the misconceptions so many ppl have about him that you've just demonstrated? After all, it is Christmas.
All I will say, is that Murphy's Law in this case is completely irrelevant.

Its like taking a glass full of water, putting a playing card over the top and turning it upside down. The water stays in the glass from the 14,4 psi air pressure.