I almost forgot to add that when I started the 12/12 I put together an inexpensive home-made co2 generator by mixing 6c water, 1c sugar, and 1/2tsp yeast. I took 25' of aquarium tube and put it through the lid of my 2liter bottle, sealed it with caulk, punched pinholes every 1/2", and ran the tube through, above, and around my ladies. I know that the co2 output for this setup is minimal, but I figured WTH! It cost about $5.