Parts per million of CO2

How many parts per million of C02 should one use in a grow room? How does one monitor the amount in the air?
Can there be too much?

Nova Scotia, Canada

The amount of CO2 the plants can use depends on the amount of light they are receiving. The higher the light intensity, the more CO2 they can use. At normal atmospheric levels (350-400 ppm) CO2 is usually the limiting factor in indoor gardens. As the amount of CO2 in the air increases photosynthesis and the growth rate rise in a linear ratio with the CO2 enrichment.

Usually gardens using around 30 watts per square foot can handle enrichment up to about 1,000 ppm. Increasing the amount beyond that level probably won’t result in increased growth, since light, the energy powering photosynthesis, becomes the limiting factor.

At 60-100 watts per square foot the plants use can use 2,000 ppm CO2. Since the amount of light the plants use for energy increases they can use more CO2, which they use as an ingredient in the manufacturing of sugar.

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