Calculation of need in CO2
An adequate enrichment of Co2 in an indoor garden can increase production by 20 to 30%, in addition to providing healthier foliage, resulting in larger, denser and heavier fruits and flowers. In addition, it reduces the time of growth and flowering.
However, several conditions must be met to obtain such good results.
- A lot of light
- Elevation of temperature (between 90 and 95 degrees F)
- Increase up to double, for water and food needs
- Sequence aeration and airtightness of the room to keep added Co2 supplement
- Ideal volume of CO2 required in the air for plants: 1500 ppm - 300 pp (present in the air) = Add: 1200 PPM
- Example (for a room of 10'x10'x10 ') is: 1000 cubic feet
Assumptions and constants:
To have an average of 1500 ppm of Co2 in the air, it is necessary to
- . 04ft. Co2 cube / day / 1ft. cube of space in the room.
- One pound of Co2 is about 8.7 ft. cube
- There is approximately 300 ppm (part per million) in ambient air (normal) 20%.
- To obtain the maximum recommended enrichment in Co2, the addition is generally 1200 ppm (1500 ppm - 300 ppm = 1200 ppm) hence the addition: 1200/1000000 =. 001200.
- 100% - 20% = 80%
How much Co2 should I add in the room to have a constant average of 1500 ppm Co2 in this room?
Method No. 1.
(daily amount of Co2 in cubic feet per day for a given space)
- Dimension of the room: height x width x length. Ex: 10' x10' x10' = 1000' cu. (1000 cubic feet)
- Quantity of Co2 in cubic feet per day required for a room of 1000 cubic feet at 1500 ppm: (Piece size x hyp. and box no. 1)1000' cu. x. 04 ft. cu/day = 40 cubic feet of Co2 per day maintains a 1000 cubic foot piece at 1500 ppm.
- Since we already have 20% of our requirements in the ambient air: Required supplement = 40 ft. cu. x 80% = 32 ft. cu. of Co2 per day 32 ft. cu. x 18 hours (75%) = 24 ft. cu. of Co2 per day 32 ft. cu. x 12 hours (50%) = 16 ft. cu. of Co2 per day
- It is known that 1 lb of Co2 = 8.7 ft. cu. (hyp and ct #2): So, 16 ft. cu. divide by 8.7 ft. cu. 1.84 lb of Co2 / day for 12 hours of use.
- Cylinder life: Ex: Cyl 20 lbs x 8.7 ft. cu. per pound (hyp. and ct 2) = 174 ft. cu. 20 lb / 1.84 lb / day capacity = or = 174/16 =10.8 day = service life
Method No. 2.
(Addition of Co2 determined by regulating the flow rate of a regulator (cubic foot/hour) according to the ppm required)
- Workpiece size x ppm desired = Diffusion setting (measurement scale expressing the flow rate of Co2 injected in cubic feet per hour by regulator adjustment) Ex: 1000 ft. cu. x. 0012 = 1.2 ft. cu. of Co2 injected per hour
- Daily Co2 requirement in ft. cu.1.2 ft. cu. per hour x 12 hours = 14.4 ft. cu. / day
- Once our daily Co2 requirements are quantified, either in cubic feet or pounds, it can be distributed in a continuous sequence or several sequences after each ventilation cycle.