Well look at it from my view, i veg 1 week solo, 2 week 2 gallon, then into a 10 gallon for 7 more weeks veg before flower. shooting for 4-6 zips a plant. I run my co2 with a tank set up and with co2 bags in the other. Seems the same lol. Idk, ive read articles from HT regaurding closed systems...