When micro organism is important to grow in an atmosphere CO2, the easiest way is to place the plate culture together with a light candle and crew down the lid of the jar and incubate, you no light burn in the present of oxygen, with this method, the candle will continuous  burning until when the availability of oxygen is used off by the burn candle and there is no availability of oxygen remained, then the candle will off, by using oxygen present in the jar warning, it yield carbon dioxide to the jar that is  the atmospheric CO2, below is the diagram.

anerobic jar

          Candle jar incubation

In the case of exact 10% CO2 is needed, the following procedure must be follow;

Place the culture plate in an anaerobic similar jar, and screw down the lid.

Fixed one outlet on the lid to a monometer and another outlet to vacuum pump, expel the air inside till 100mmHg reading is achieved on the manometer. Close the vacuum pump tap and then fixed it a carbon dioxide sources.

Free the carbon dioxide to enter the jar until 24mmHg reading is obtained with monometer.

Both tap should be close and jar now should be taken to an incubator, when taken to incubator open the tap so that it will permit worm air to enter the jar. Them closed the tap and leave it to be incubated.

NB: when alter vacuum was achieved in a jar, the manometer reading will be at standard pressure which is 760mmHg in these case 10% of atmospheric pressure will be 76mmHg.


Now by extracting up to 100mmHg and introduce CO2 until the manometer reading clock 24mmHg, at this point 10% of atmosphere pressure has been replace with CO2.

By unclose the tap in the incubator, warm the culture and also permit homogenous mixture of CO2. These occur do to the air present in the jar, when these methods are properly adhered to, a required volume of CO2 can be replaced in the jar.

Toil sachets are available commercially, as it was stated earlier it is been for CO2 generation into the jar. The instrument is easier to handle easily dependable.

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