My apologies for bumping this 6 month thread, but appreciated the advise in the first post about this method.
Even though I have a 20lb Co2 tank and regulator, I decided to try this method as I'm tired of shlepping my Co2 tank to get it filled. So for a couple weeks I'll use this method. (Just tinkering with the sugar/yeast Co2 method as I like to experiment, last month I expiremented with the CREE XLAMP LEDS for lower foliage illumination, that went well, so now I'm tinkerin with this)
I did however change it a bit and used a bit more sugar and yeast in the two liter bottle. I had to tape the aquarium tubing an extra 6" in a vertical position as the reaction in the bottle was creating more Co2 than expected, and the vertical tubing has a added bonus, I can see the Co2 going up the tube in an constant Co2/water bubble every few seconds. To finish this, I simply placed the aquarium tubing to the center of a 92mm quiet Papst dc fan (
Running it at 8 volts) that blows the Co2 across the top of the plants. Haven't decided if enough Co2 is created to use the normal Co2 tubing with all the holes in it. Later I'll test the C02 with one of those Co2 testing kits. Then maybe add a couple more two liter bottles to see how much C02 is viable.
Also will be hooking up a better fan later today, I have a
Sanyo Denki counter-rotating DC fan that has better airflow dynamics than that of a traditional fan like the Papst I'm using at the moment.