Why does new carbon fizz?

[Cypherman]

See title...:D

[RustyRay]

Because activated carbon contains millions of tiny holes. And when water fills all those tiny holes the air escapes rapidly which creates the fizz you are refering to.

[Cypherman]

Aaaaahhh, that makes sense...Just something I've always wondered about :rolleyes:

[fishdude]

well mine steams and fizzez and gets a little warm air wont do that

[RustyRay]

Activated carbon also reacts with water, adsorbing elements and compounds from the water upon contact with it. In the chemical reactions, chemical bonds are broken and energy is released in the form of heat. So we have water rushing in, air rushing out, and heat being released.

[Cypherman]

Yea I always assumed there had to be some kind of reaction taking place because why woud they tell you to rinse it if it just fizzes? Activated carbon is pure carbon, right? And coke does react with steam to produce carbon monoxide and hydrogen, right? So maybe the carbon powder produces a reduced version of the above reaction...Those definitely arent gasses you want in your tank, so maybe thats why they always tell you to rinse it first.

[RustyRay]

Well, it's not a burning reaction, like the kind that produces carbon monoxide. Carbon readily bonds with many other elements. So activated carbon adsorbs many elements too. Initially carbon adsorbs a lot of oxygen also.

I think the reason it it a good idea to rinse carbon is to remove the dust and to fill it with water. I've mistakenly forgotten the rinsing and placed carbon in my tanks without any ill effects on the fish or plants. It just threw a black cloud of carbon dust into the water.