c02

[Zandor]

1500 ppm, 5000ppm or 25000ppm -- how do you know, using yeast, a coleman lamp, or soda? There is no formula for these, and environmental issues such as air leaks and temperature would render a formula useless anyway. You could be completely out of the effective range with these methods, making your effort a total waste of time and money. You could also be damaging the plants. You are completely out of control. There's no way to tell without a monitor, and no way to start, limit, or stop the flow without a regulator.

Any way you look at it, the bottled co2 is the way to go.

How do I know? I do; I mean it's been researched and reported many times. Written in grow journals and books for many years. I have several controllers my self and do my own research but when people with PhD at the end of their name tell me so I have a tendency to believe them. Don't be so arrogant in your replies you are wrong as much as you are right. (I'm trying to be nice here).
I agree bottle CO² is great and having a controller is wonderful and controlling the environment is what I preach here everyday. But CO² is one of those things where even a little is better then nothing. Hell 99% of the people can't produce enough to do any harm anyway. Controlling CO² is the way to go but that does not mean if you can't afford the whole setup you should not do something.

There are many formulas around, hell even I have posted several of them here myself for people. Even though I don't need to use them anymore.

You can use math to caculate the amount of CO² build up you need.
http://www.hydroponics.net/learn/co2_calculator.asp
They have a nice calculator you may find helpful.

Normal air has about 300 ppm on average so if you produce 500 ppm then your plants are receiving 800 ppm of CO² and that's better then nothing you must admit that fact.

It's not a total waste of time and money now is it? The only real waste is not to try and not willing to learn don't you think?

It's a hobby and playing is half the fun.:dance: