By mixing an acid and a base in a pressurized cylinder designed for this use, you can have a supply of C02. Using a valve and electric actuator we can use a C02 metering device to allow the gas to flow into a grow tent or green house.
These C02 generators can be purchased on Amazon and are made for this, explaining how much Citric acid and Baking soda to mix. Using an AC infinity C02 controller we can monitor and meter how much the tent gets. Seems most people are using these for their aquariums, but my use will be different.
It comes in a kit with everything needed besides the acids and bases.
We can see directions on the top of the gas cylinder. Mixing 360G of Citric acid with 400G of baking soda and 600ml of cold water.
More instructions are on the bottle explaining how to use. Good points about adding cold water, if use you warm water the acid and base react faster and you may have a foam over before you can get the cap on...lol
Important to note you must let the reactants settle otherwise they will get pulled up through the valves and possibly clog it. So once you add the mix, you let it sit for 24 hours to build up gases and let the solids settle.
The top has a pressure gauge to tell you once it has built up enough pressure to allow gas flow through the system.
A day later we are ready to raise the C02 in the tent.. Baseline is around 700.
I turn the valve and we can see gases bubbling up through the viewing glass.
A few hours later we are up to 940PPM, well above the ambient.. its working. I had to stop the intake fans to the tent to get to this level, so the temps inside the tent slowly rise as the C02 builds up.
Shortly after we cross over 1000, with the goal of around 1200PPM
Eventually it gets up to 1100PPM but due to the tent temperatures I had to allow air flow in, which quickly dropped the PPM.
I can see myself using this setup during the winter, when the basement temperatures are low. Otherwise it is hard to keep safe temperatures inside the tent without exchanging air flow. I guess a timer would work well to flush out the air once in awhile and allow cool fresh air in. So something that has a timer that will come on after a set amount of time and then turn off in cycles would fix that concern.
I would need to buy a second tank if I was to use this method throughout a grow. As they only last about 24 hours, I would need to have them in rotation. So as one is empty I have a charged one ready to go. Otherwise the downtime of 12-24 hours would occur while I wait for the next batch of acids and bases to build up C02.