http://www.aquaticplantcentral.com/g...2_original.jpg

Theres a simple image of it. I am useing this method. Can't say 100% if it works good or not as this is my first grow and I have nothing to compare to. But I only get about 1 to 2 bubbles per second in the water bottle. When I shake the 2 ltr bottles I do get a burst but once that goes away it's back to 1 or 2 bubbles. It's nice to see cause you know something is taking place inside those bottles.

You need to stop co2 flow to your growth chamber during dark period, because the process works backwards when lights or off. When you turn the lights off, you make the plants stop doing photosynthesis and start growing by using the product of photosynthesis. They do that by using oxygen, so you need to stop co2 and change the air when the lights or off. this should increase the growth of your plant significantly in theory.
Another point, I don't think you need 100 bottles of yeast for a regular sized growing chamber. Because the co2 percentage of air is quite small, so throwing in a bunch of bottles should increase the co2 percentage significantly...