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Re: [APD] CO2 mist and the persistence of the micro bubble

Thomas Barr wrote:

> You are adding CO2 to a solution that is already heavily super saturated.

I don't know about that. At room temperature CO2 has an approximate 
solubility in water of 900 cm3 per liter*. That's about 370g for a 
55-gallon tank. Anyway, 900 cm3 of CO2 per liter amounts to somewhere 
around 0.04 mol/l, or about 750ppm if I'm not mistaken. That would make 
30ppm only about 4% of saturation.

> I'd suggested it was O2 at one point, the flame test was not conclusive(it put the flame out, suggesting CO2, not O2).

Organic material will not burn below about 16% O2.

> So this means, and I know I'm right(rare), that the CO2 dissolving is greatly reduced later at a stable given CO2 dosing rate in the day after you build up to a certain level. What level? I'd guess about 30ppm.

I'm curious to know why you guess that amount?

> After you get this into the tank( 30ppm dissolved CO2), then this CO2 micro bubble theory starts to work. You still have 30ppm in the tank, but now you have added pulse of pure CO2 mist on top of that for the plants.

I still don't see how increasing CO2 above the level where 
photosynthesis is saturated will increase photosynthesis.

* http://scifun.chem.wisc.edu/chemweek/CO2/CO2.html

Jerry Baker
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