ENCATUSE I definitly agree with NOTANOVICE in regards his suggestion i have used the yeast method before and found that it worked great cant remember how much i got but i know i did better than expected if u want to know my formula for this inexpensive way of producing co2 and all the things you will need post a message under my thread THEY CALL ME MR. KNOWITALL in the INTRODUCE YOURSELF forum and i will get back to you asap cool GROW BIG OR GROW HOME.