DIY - Projects & Ideas • Awsome and unique Fish Tank

[armenhamer]

I came across this tank on youtube. There are actually 3 of them. I believe if you take the time to look, this will certainly be worth a discussion. go to youtube and search for, ( fish tank open bottem). Have fun!!

[~laura~]

http://www.youtube.com/watch?v=5InNVJ_Ythc

[CDMOK]

Link to save everyone else a hassle: http://www.youtube.com/results?search_query=fish+tank+open+bottom&search_type=

I'm not really sure how I feel about them.

[Rift485]

I think that's a cool idea and you could do a lot more with it than he did. I especially like the music

[a_c_arnold]

Looks like a power failure would flood your house. I would be interested in seeing some of the operational principles behind this tank. Vacuum system and air removal system.

[TabMorte]

Wouldn't that be really hard to keep clean? Since the raised bit would spill every where if you had to open it up to clean it?

[Mcdaphnia]

There was a long discussion about these before, and some people felt they were a PhotoShop creation. If you did invert a tank over another one large enough to envelop it, you would have to put the air pump inside the air space at the top of the tank, or every air bubble would displace water until the inverted tank was dry. Which means you are recycling the same air over and over depleting it of oxygen and building up CO2. Might make a great planted tank with all that CO2, but hey there's no substrate!

[armenhamer]

I'm thinking that maybe their is an airhose running down from the upper tank air space to the bottem tank and then out into the air, equalizing the incoming air from the airstone. I'm going to try a few tests in the kichen sink with a jar. I understand the water staying in the upper tank but not when you pump in air because then you are replacing the water with air. I really don't believe it is a hoax.

[jwal]

well from a little experiment i did in the sink ... any tubing running from the enclosed air space to the outside air would cause air from the outside to flow into the enclosed air space due to pressure differences. So, you would need an air pump removing the built up air that could prevent the backflow of air as it was removing the air. possible? probably not with a cheap aquarium air pump...

[acrosstic]

This is easy to explain, the air pump is located in the top section of the tank, therefore the air being pumped into the top section of the tank is not exiting the top of the tank. It iss returning to the top of the tank and the pressure is not changing.

It took me a minute to figure it out.

If the pump goes out, the pressure doesn't change either, so you don't get a flood.

The trick is filling it up. He probably had to use a powerful vacuum to remove the air in the upper tank while at the same time filling the lower tank. Once it is set-up, it isn't a problem.

Her is the catch: If the tank level falls below the bottom edge of the upper tank front glass, air will be allowed to enter the top of the tank, and the 130 liters will flood the 120 liters tank below and it only looks like he gave himself about an inch of leeway.

I'd design it so the upper tank couldn't flood my house.

Say 150 Gallons in the lower and 50 in the upper. With the 50 gallon glass extending half way into the depth of the 150. That way if the tank water ever did fall below and the front edge of the 50 and it emptied it might splash a lot, but not flood my house.

The biggest risk factor would simpyl be evaporation.

[acrosstic]

I thought about it more and I suppose the water would only flood the lower tank enough to fill it back up enough to create the vacuum again. So all it would really do is create more air space in the upper tank, but not flood. Then you'd have to suck out the air in the upper tank again.

So there you have it.

[Mcdaphnia]

I'm thinking that maybe their is an airhose running down from the upper tank air space to the bottem tank and then out into the air, equalizing the incoming air from the airstone. I'm going to try a few tests in the kichen sink with a jar. I understand the water staying in the upper tank but not when you pump in air because then you are replacing the water with air. I really don't believe it is a hoax.

I think in the old discussion on this someone with video knowledge did some technical analysis which he said proved that these videos were two tracks combined in the same way you see an actor or actress carrying on a dialogue with themselves on the same screen, like Parent Trap.

As to having one pump bubbling in, and another one bubbling out, it would be impossible to balance them exactly. When my son was in junior high school, he frequently demonstrated how it was impossible to balance pumps by flooding his fish "closet" which prompty drained into his mom's walk-in closet. She would usually discover this first thing in the morning by stepping barefoot onto a saltwater soaked carpet. If I wasn't awake before, I was after! It is much more believable to have the air pump located inside the aquarium in the airspace and recirculating the same air.

Bottom line. This could be done, but not quite as it is portrayed, which appears to be faked. The thing that made me suspicious were the little things done with the net and fish to convince the viewer that this was a real setup. If it's a real setup, why would you need little tricks to convince anyone? You'd simply show the details of the system, which are assiduously avoided.

The problem with doing it is the impracticality of maintenance and its unreliability. It would be a great display at a weekend fish show, (with lots of mops and buckets close by) but would not make a permanent set up.

[aaxxeell]

the system is based on the romaurie effect and yes it can be done, the top of the tank is sealed with a outlet port for air, the air pump is more the size of an air compressor in a closed loop, meaning the air thats sucked out the top of the tank and put back in there via the airstone so theres never a catastrphic flood.

not quite sure how to do proper waterchanges tho, +vacuming the substrate would be darn near impossible.

heres another interesting wacky tank that uses the romaurie effect slightly different:
http://thecontaminated.com/pipeline-fish-tank/

[Mcdaphnia]

the system is based on the romaurie effect and yes it can be done, the top of the tank is sealed with a outlet port for air, the air pump is more the size of an air compressor in a closed loop, meaning the air thats sucked out the top of the tank and put back in there via the airstone so theres never a catastrphic flood.

not quite sure how to do proper waterchanges tho, +vacuming the substrate would be darn near impossible.

heres another interesting wacky tank that uses the romaurie effect slightly different:
http://thecontaminated.com/pipeline-fish-tank/

Yes it can be done, but not quite as pictured. The description with the video says there is a vacuum pump and an air pump, not a compressor, and a water pump for filtration. Here is a pic and details of a working inverted tank, a little different, starting with the heavy glass needed.
http://www.instructables.com/id/Romauri ... hallow-ba/

[cichlid_junkie]

I would think that very low pressure at the top of the inverted tank would make evaporation a serious problem.

Just my 2 cents.