yeah its ok to lollipop and prune mate at week 1 of 12/12 and week 3. it shouldnt have any ill effects on your plants. if ur using the flora series u should increased the feed to a 3-2-1 ratio ( grow micro and bloom .... in that order up... to an ec of about 1.2 ). do this for the 1st 2 weeks then change onto your flowering feed which a 1-2-3 ratio ( grow micro bloom ... with an ec of 1.2 ) increase that ec every week from then on by 0.1 until the last week of flowering then just us PH balanced water for the final week. the hairs should start to show anytime between 14 and 21 days mate ... theres no need to panic. also always make sure ur ph is right ( i find 5.8 works best for me). one final note mate and this was a piece of advice i got from Soma back in 2009 at the cannabis cup in amsterdam ( i have a friend who is very good friends with him) but anyway he told me that when i thought my plants where ready to give them another week with the last 3 days in total darkness and i must say when i tried it it made a hell of a difference to the white widow i had been growing for years.

i hope i havnt waffled on too much mate ( kinda stoned at the minute ) its always a learning curve growing weed mate but keep it simple and give them what they want (i.e food and light) and u will always get top results .

i hope this helps

Hal