# I'm sealing my aquarium!



## Flun (Feb 7, 2009)

I have this really radical idea  .....ok maybe not, but it seems weird to me, so if anyone can tell me it what it is I'd be happy.

I've read much about surface agitation (which I have lots of) and CO2 I have started to think that my CO2 diffusion isn't good enough in my 2g nano, no pearling on the HC and I don't trust my tests that say levels are good because I have wood in the tank. My new idea is to partially "seal" the tank with a glass lid so that the water is directly against the glass lid, my tank let's me do that pretty easily. This way, there is only a 1.5x20 cm strip of water that has contact with air. The CO2 bubbles that do rise to the surface instead gather against the glass lid and with water flowing under the bubbles my guess was they'd be diffused. 

It's a plants only tank...
Is there something I'm not thinking of here?


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## Diana K (Dec 20, 2007)

O2 will not diffuse into the tank, and this would become a problem for the fish at night. I have inadvertently done this by overfilling a tank, and the fish are gasping the next morning. 

You have the right idea, trapping the CO2 and allowing it to diffuse into the water at its own rate, but just use an diffuser designed to do this. Suction cup to the side of the tank, and it is like an upside down bowl. CO2 bubbler under it, so whatever is not diffused into the water right away gets trapped by the bowl.


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## Quetzalcoatl (Feb 13, 2009)

This should be OK since you have plant only tank. Though, I would be concerned with micro-organisms and bacterias. Most of them require oxygen to survive. Sealing your tank can easily over dose CO2 and tip the balance you established. Have you considered using a diffuser?


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## Flun (Feb 7, 2009)

Thanks for the answers, I diffuse by leading the gas into a pump impeller and I can see bubbles throughout the tank so I guess it's an ok kind of diffusion on it's own, I was looking for a way to make it even more effective. I am concerned about micro-organisms as Quetzalcoatl said, what would happen if say, I had a lot of bacteria dying, short term consequences?

I have a fast build up of... well, dirt on and in the substrate. I thought I saw an increase of it when I "sealed" the tank. How could it be related? It's a non-filtered tank so I sort of expect some extra waste, if that's what this it, but it builds up much faster than I had expected. Is it just dead micro-organisms and waste or could it even be some kind of algae?










Thanks for reading

(Here's the whole mess if anyone's interested http://http://www.aquaticplantcentral.com/forumapc/nano-aquariums/61978-my-newbie-effort.html)


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