This is a brief method of how i do my DIY C02 yeast mixture.
2 litre bottle
Air line tubing
2 caps to fit the tube
first of all take the 2 litre bottle lid and pierce a hole with the drill. Ensure that the surface below the cap is protected or it will be damaged. Ensure the drill bit is a little smaller than the straight air line connector.
Once the hole is made insert the air line straight connector and pull into position with pliers. This seal should be airtight but i add a little silicone.
It should look like this
Now to make the mixture
Measure two 400ml jugs of sugar.
place into a bowl and add a small amount of boiling water and stir in the sugar until its all dissolved and the mixture is clear.
Add some cold water to make the mixture lukewarm and add to the 2 litre bottle. Next take 250ml of lukewarm water and add one and a half teaspoons of yeast and gently stir.
Leave the yeast for 2 minutes. Add 1/2 a teaspoon of baking soda and stir.
Add this mixture to the sugar mixture in the 2 liter bottle and top up with lukewarm water
The mixture is complete and will produce C02 in between 5 Minutes and hour and half.
I then attach air line from the top of the lid to a gang valve to allow me to control the flow of CO2. It then connects to the bubble counter. Between which i add a t air line connector with a gang valve on the end. This is used at night when the C02 is off as a precaution so that there is not a build up in pressure in the bottle.
I make the bubble counter from a tube from an aqua one sponge filter in this case and add the two cap ends. These have been drilled for an air line as the bottle lid has with the mixture in. I then add a short piece of tubing to the base with a straight connector on the end ensure that the connector is on the end that is inside the tube. To the other end of this tubing i add the check valve ensuring that the flow is in the direction of the tank. The other end of the valve is attached to the aforementioned gang valve which comes from the C02 bottle with air line tubing. At this point fill the tube 3/4 full with water. I then add a air line connector to the top cap followed by air line tubing. I then silicone around the top and base cap. The air line tubing from the top is then attached to the venturi outlet on my filter and the C02 system is complete. The gang valve is used to determine bubbles per second.
Two weeks setup plants were tiny when i got them.