CO2 - Lighting, Exaust, Seedling and Fetus stage, Purple Buds, Early Flowering

Ok, so I'm planing on building the homemade CO2 distributer from the Sticky thread in General Marijuana Growing, except with honey instead of cane sugar for obvious reasons. Anyways, so first my plants are 8 days old 18-6 under 4200 lumens/sq. ft. with 50 CFM intake and 50 CFM exasut in a 12 cubic foot grow room. Are my plants to young for CO2 treatment? With my aircirculation is it reasonable to poisen my plants with to much CO2? Do i have too much air circulation for the CO2 to make any effect? With this lighting is CO2 a waste of time and energy? I'm trying to grow my buds purple, will the CO2 effect that positively or negitively? Will i need more nutrients with CO2? And i am flowering at 6th set of true leaves, with this early flowering is CO2 a waste of time and energy? And is there anything else i have too worry about fucking up with CO2? Will my plants get to big with LST and CO2?
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