CO2- Veg vs Flowering

Hey all, I have heard that people do not use CO2 in the last two weeks of flowering, can anyone confirm that this is good practice? Also, should the amount of CO2 be more or less in flowering than in vegging? I am growing in an aeroponics system. Any one's experience with these issues would be greatly appreciated. Thanks!

The amount of CO2 and when to use it depends entirely on the temperature in the grow room. For an example if your temperature are in the low seventies and you have a ventilation system you will not gain by CO2 usage regardless of the plants stage of growth. CO2 supplementation is only beneficial when otherwise there would be a shortage of CO2. This shoratge only occurs when light, and nutrients are provided in abundance and the temperatures are above the mid 70's even with ventilation. CO2 supplen mentation should only be done in seales temperaturecontrolled rooms. Typically it is only used by commercial growers due to th increased expense of air conditing/dehumification. It doess however increase yield and the incraesed temperatures speeds up the rate of growth so more grows can be done per year. For a good CO2 system that is metered figure $750 for a full installation with two tanks, regulator/solenoid, timer and a monitor/controller. Then add on at $250 for a dehumidification/air conditioning and a good thermostat. Not an investment most newbies or small growers take on, even though the yield increase is usually 50% or more.

The only reason not to use CO2 during budding would be the fact that using CO2 always increases the humidity as it increases respiration and the elevated temperatures increase transpiration. Unless a dehumidifier/air conditioner is used there is a good chance of the buds having a rot and fungus problem.

Here in So cal we have low humidity usually no greater that 30%. I plan on using a co2 setup and a humidifier as well to keep humidity around 60-70% during the day and then turning everything off at night to allow the humidity to drop to avoid mold and rot.