2 weeks flowering..yellowing leaf tips

Im using 3x25w CFL's

I vegged for 2 weeks and did some LST

Temps are around 68 at night and 74 during the day

I just started using some nutes because I thought it might solve the problem..no change. Its in organic soil and watered often. Let me know what you think

you need more N or it's over nuted can't really tell from the pic

It turned out that the plastic wire around the plant stem was starving the upper plant..glad I noticed it in time!!

Update!! (4 weeks flowering) no improvement

More pics to help with analysis, more opinions needed please...

Can you get those lights closer and monitor temps near light canopy.