How to set up a DIY Yeast CO2 System for your aquarium ?

Are you interested in making your own CO2 system for your aquarium? It may not be the best CO2 system around, but it is sufficient for most middle to small size tank. Before getting into the steps of making this CO2 system, let us first understand how this thing works.

Yeast are simple, unicellular fungi. They are like most fungi, respire oxygen (aerobic respiration), but in the absence of air they derive energy by fermenting sugars and carbohydrates to produce ethanol and carbon dioxide. Thus you will sense a strong smell of Alcohol when you pour away the old reactor and refilled it with new ones.

Item needed:
1) A big soft drinks bottle which a volume of minimum 2L.
2) 2 meters long of silicon tube. Can be bought from Local fish shop.
3) A packet of baking yeast from the super market.
4) A packet of sugar (get the cheapest one will do)
5) A silicone sealant
6) Water ( 70% of the bottle)
7) A diffuser

Now let get into the steps of making your reactor.

Step 1: Drill a hole into the cap. I do it by using a screw driver. Heat the screw driver up with fire, and screw a hole in the cap with the hot screw driver.

Step 2: Cut one end of the tube to a V shape. Attached this end into the hole.

Step 3: Seal both the sides of the attachment with silicone sealant. This will prevent the co2 from leaking out.

Up to this step, the reactor container is complete. Next is do to some mixing of elements

Step 4: If you are using a 2L bottle, pour around 300-400ml of sugar into it. I uses ml here because i am using a cup as a gauge.

Step 5: Put 2tea spoons of yeast into the bottle.

Step 6: Fill the bottle up till its 75% full.

Step 7: Shake the bottle. If you have another similar bottle cap, it can be used for covering before shaking as the original bottle cap is being attached to the tube.

Step 8: Cover the bottle with the cap that is attached to the silicon tube.

Step 9: Attached the other end of the tube to a diffuser. The diffuser can be a bell, a air stone or a commercial type i show in the picture.

Bingo! The cO2 system is complete. Give it some time to generate the cO2 and the system will generally last around 3weeks.


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