[Hoppy]

Yeah, I'm not sure either. But chemically speaking if you fully diffuse CO2 in H2O you get H2CO3, and no bi-products, soooo.... what's the difference to just adding straight carbonic acid?

(

Not true. If you saturate water with CO2, you have a mix of dissolved CO2 in water with a little carbonic acid and some carbonates, depending on the KH of the water and the temperature. Dissolved gasses are not molecularly combined with H2O, just dissolved. Similarly, if you saturate water with oxygen, you don't get hydrogen peroxide, just water with dissolved oxygen.