How to build DlY you can find youtube.
DIY co2 Recipe
1. Bring 3 cups of water to a steady boil then pour into a suitable container
2. Add 2.5 cups of sugar to the water and stir vigorously then place it in the grow room.
3. Mix a teaspoon of baking soda with 3 cups cool water and add to the hot water / sugar. Yeast dies in hot water and will not activate in cold water. The best water temperature range for yeast activation is 100 - 110 F.
4. Add three 1/4 oz. packs of dry yeast. Distiller's yeast works best, it lasts longer but bakers yeast will suffice.
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