Ok heres the deal my 1st timer, trim the old yellow leaves in order to penatrate the new bottom buds and LST (low stress training) if you want to reach the buds with enough light to the bottom buds. 3ft is about right 4 NL, dont worry how far is ur light from ur top of ur plant? Just make sure its close, do the test. Put ur hands to the height of ur plants, if its to HOT 4 ur Hands then its to hot 4 ur plants. Reg temps is 70-87%F, have enough fresh air and you'll B OK..... GOOd Luck

PS... Do a search on OLD growers mine, Mobays , Mand, Turtle etc.....

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