So I decided to go the DIY CO2 route for my tank as it is a low maintenance cheap on the fly DIY setup and so far after some trail and error I think I finally got it down. What you will need is the following: 1. 2 litre Coke bottle label removed and washed and left out to dry. 2. 1 litre Coke bottle label removed and washed and left out to dry. 3. Airline tubing +- 6 meters depending on your needs and non-return valve. 4. Air-stone and two suction cups and some marine silicon. First you take the cap from your 2 litre bottle and drill a hole in it so that the airline tubing fits snugly into it (make sure it sits flush with were the bottle cap ends when you screw it onto the bottle), silicon both top and bottom parts were the airline tubing meets the cap, make sure not to get any of it on the cap thread. Then take the 1 litre bottle cap and drill two holes in it. The tubing from the 2 litre bottle goes into the one hole (Make sure it goes about halfway down into the bottle) and do the same you did with the 2 litre bottle. Then somewhere on your airline attach the non return valve and on the end your air-stone with a suction cup. So basically you will end up with a 2 litre bottle that has a tube running from the 2 litre strait into the 1 litre and from there another tube running from your 1 litre to your valve and then your air-stone. Now fill your 1 litre with water till the piece of tubing is under water. We do this so that when the CO2 is produced whatever particles and other things that might pop out of it that the water will catch it and that we get clean CO2 out on the other side. Ingredients for CO2: 2 cups sugar. 1 tsp baking soda. (Reason for baking soda is it stops the water from going acidic which kills the yeast) 1/2 tsp yeast. How to Mix: Start with a small bowl and add a small amount of lukewarm water (Not hot as it will kill the yeast) and add a teaspoon or two of sugar. Mix in the yeast with a fork, stirring regularly until bubbles form on the surface. This will help to "activate" dry yeast by adding oxygen, preventing mass die-offs that occur if you just throw the yeast into the bottle. Let this sit for 10 minutes. Now add the 2 cups of sugar and a table spoon of baking soda into the 2 litre using a funnel. Fill it about 2/3 of the way with lukewarm water. Tap water is fine, put on a cap and shake till all of the sugar and baking soda has dissolved. Then add the bowl of yeast you don't have to mix it just put on the caps and make sure they are secured properly and store them near your tank. I use the mixture of 2 cups sugar and 1/2 tsp of yeast. ore yeast means the mixture will produce a lot of C02 but not last as long. So with this 1/2 a tsp it produces a constant C02 for a longer period of time, I would say for 3 weeks and the 1 tsp mixture lasts 2 weeks or less. It should take and hour or two to start producing. It may take a day depending on the temperature of water you used in the mixture.