Help!Leaves Are Curling And Burnt

i am having some problem just as i am about to start the flowering cycle. some of my leaf tips are looking burnt, there are also some leaves that are really curled and i havent seen this before and i hav done alot of research on this site and cant figure it out. this is my first grow also so i am panicking slightly. i am growing under cfl 250watt and it is about 3 inches away from the plant tops so i dont think they are too close and the temp in there is about 21.5degreesC so its not too hot . ihave added nutes just today at half strength i water them every three days. here are some pictures you can see the damage very well you ca also see the curling on one of the plants on a side view shot. any help would be much appreciated. if there is anything more you would like to know about my grow please ask

looks like a bit of nute burn, not too bad though....... i had the same problem, and i flushed and within days it was gone...... it isint too bad so if you fluhs now, there shouldnt be too much damage..

yeah but this was the first time that i have added nutes i thought it might be happenin because i hadnt added nutes. there is some slight yellowing also on the edge of some leaves. im stumped

sounds like lack of nutes, what are you using, what is the ph of the water when you water plant, what is the soil ph?