geez dude, you couldnt of searched too far, I posted this afew days ago.....
some people have asked me about dryice, and I thought I'd look into getting some informative answers for everyone.
One of the benefits (however small) is the cooling effect of dryice, since it is -80 degrees, also be very careful handling dryice, as it will burn you at that temp.
Dryice is generally available in 50lb blocks, and can/should last about a week, depending on alot of factors. Placing a small cooler in your growroom to store the dryice is necessary, either open the cooler during lights on hours, or I take it out and place it on top of the cooler, and place it back in the cooler near lights out.
Cost varies ALOT, depending if your getting it from a supplier or a manufacturer, going to the source is always better.
From what I know, and I've been handling dry ice for about 25 years, cost should be about $15.00 for a 50 lb block.
This should last about a week.
One pound of dry ice will produce 8.7 cubic feet of gaseous CO2. You’ll need to provide about .04 cubic feet of CO2 to the garden per day for every cubic foot of grow space. That means that a 1 pound block of dry ice will provide one days coverage for a 217 cubic foot garden, which is slightly larger than a 5’ x 5’ x 8’ area. The trick is to leave the cooler open just enough to let the dry ice sublimate at the rate you want.
If you produce more than this amount, it will not hurt the plants at all, but be ready to "read your plants" and know when to water and feed them, as they will need extremely larger amounts of nutes.
Another side benefit of this method is that you will not have a problem with insects at all.
I loved using dryice, as I can see the benefits immediately. ALWAYS feed your plants well prior to using dryice.
