How is this done?
 

Okay, I know it's not reef related but does anyone know how this tank works. To me the water level should be equal in both tanks.

Is someone using trick photography.

http://www.youtube.com/watch?v=8s81g...eature=related

Nope its not a trick. Because the "vertical" tank is sealed and not letting any air in, the water in that tank is "trapped" and has nowhere to go due to its submersion under the water of the horizontal tank. I can't remember what scientific principle this is called. Try it with a full pop bottle, immerse the open end in a sink full of water. The water in the pop bottle won't go anywhere unless you pull it above the level of the sink water so air can get in to the bottle.

I'm trying to think of practical uses and all I can come up with is my cats "auto water bowl". Basically the same principle, upended 2L water bottle in a dish of water, the water dish is always full until the 2L is empty.

I can see that, but there is air being pumped into the vertical section, where does that air go?

There is a pocket of air I think already in the top tank.

it's just pushed down and returns to the top.

I would assume there's a pump of some sort preventing air from building up in the column, a check valve is also likely used to prevent failure. Definitely a risky system though, I'm not that brave.

there can't be any air goi ng into that or it will reduce the vaccume which is required to hole the water colume up in the tank. Personaly I think it is done with Mirors other wise he would need to plumb a vaccume pump into the top of the tall tank to remove air and maintain the vaccume.

Steve

Has to be this.

And too risky for me. A pump/power/check valve failure means a lot of mopping...

Possible
 

On utube there is DIY that shows you how to biuld this tank.

As cool as that looks I'd think it's a rather large flood waiting to happen.

if you placed a mostly full pop bottle of water into the sink upsidedown quickly, the water would stay in the bottle. Could you not then have an air pump with the input inside the bottle drawing from that air cavity at the top? Blow this air into the bottom of the bottle so it just goes right back where it came from?

It is cool looking, but with any failure in the system I would not want to be the one cleaning up the mess.

Yes but I would be concerned about eventual oxygen depletion from recycling the air. Although there may be enough gas exchange from the 'open' areas of the tank.

Go
 

Depends on how the tank is setup, it wouldn't be a big mess.

If you fill up the bottom tank, setup the vertical part, and vacuum the vertical part, you basically guarantee that if it fails, all the water would be sitting in the bottom tank. The water probably wouldn't splash either because of the vacuum that has been setup at the top.

If the vacuum is stable, it technically will hold, since the only way that water will get out of there is by new air coming in. And basically as the new air comes in, the same, small volume of water water would be pushed out.
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CD175

I think that's exactly what's being done for this aqaurium.

Interesting ... I bet that's it. I was thinking it was maybe a panel of glass separating the air curtain from the vacuum side but I bet you're onto something there. A "closed loop" but for air instead of water. :lol:

Yeah that's what I was thinking but you would need one hell of an air pump. That tank looks 4 feet tall, that's a pressure of 4 feet of H20 the pump would have to overcome. And I think it would have to be more along the lines of a venturi as an air pump wouldn't last too long with the moisture and humidity it would be exposed to in this situation.

I guy could probably use a float switch to activate some kind of vacuum system when the air pocket got to a certain size.

If you look at the top of the tank he has a line drawn at the fill point of the waterline.

I also think this is done wiht mirrors. one scene the fish are in the top half then it cuts and they are all in the bottom. then when they swim under the top part they disappear. you can clearly se the top has a bottom pane of glass.

Tank
 

http://www.youtube.com/watch?v=Z7tq4LRurMs
This shows how the tank was built. No tricks, this works.

That's exactly how I think it works...and that it was very clever to come up with it.

Thanks for that great link. That explains it. Cool concept if you like to take a chance or two. :lol:

However it works it's pretty lame in my opinion!

ahaha... that guy would prob say the same thing about your tank