omg !!! i hate it when people tell me what to do and not tell me why thank you for exsplaining !!!Dude, especially with the longer light you should repot those plants before the roots get to tangled into eachother. As they grow they'll start to fight for nutes, oxygen and light which will limit growth, and odds are one of those plants is a male which will polinate your girls and turn them into shit. they're small enough right now that even plastic cups with holes punched in the bottoms will work. Just do it soon and you will save yourself the headache your heading for in a few weeks.
Whats that water bottle with the air hose to the plant for? Never seen it before
yea and dont put dry ice in a bottle with a cap on if you do run or dieUse yeast. Check out the DIY section of the growFAQ