So close, yet so far....HELP ME!!!!

Hey guys, First time grow on the go:
- Nirvana brand white widow seed
- growing in a soil/perlite mix
- Under 250watts of 2700k cfls (vegg'd under the same amount of 6700k's)
- Currently in my second month of flowering....plenty of buds well on way.
- Feeding it a 1:3:3 mix of cacti ferts (hopefully gettin summit more suited this week comin)

Now to my problem, noticed several weeks ago that a few of my older fan leaves started to produce a yellowish/brownish colour throughout the veins and this spreads causing brown and yellowy colured spots....i was not overly concerned as it was one or two leaves, now a week later i can see that it is getting much much worse.

I have looked at other threads with the similar problems and its so hard to get a straight answer so im hoping the pictures im providing will help someone to identify the problem i have...



I've heard several people say, it could be mites, root bound, magnesium deficiency...if someone could give me a definitive answer i would fucking love you for ever...heres some pics of my babe in its full glory.



Please dont bash my operation....i've done best with what little money i had at the time...please, if you can...HELP!!

See how your stems and veins are turning red? Since you are in flowering and you are using a 1-3-3 fert, I am going to say you more than likely have a PH lock up or salts at this stage. Here is what I recommend that you do to remedy this situation. Flush the plants well with water with a PH range of 6.0. Flush until perlite is bright white and water is running clear. I would also recommend a fertilizer with more phosphorous, especially for flowering. Even Miracle Grow Bloom food is better than what you are using. cacti and weed have different needs and your plants are missing out. carefully monitor PH run off and make sure it stays between 6.0-7.0 Adjust water PH accordingly.

Good luck and good harvest.