36 days into flowering. need help!!!!

Help,
I am sorry, I cannot get any pictures of the problem. Our girls are 36 +/- days into flowering and looking great. The flowers are filling out nicely and trichs are starting to swell. Using MG organic garden. they have received one dose of bloom+vigor ferts yesterday. other than that the whole 12/12 was pure h2o. The girls up to this point have done nicely and been healthy. Now, like usual, leaves are starting to turn yellow. More leaves than I think is healthy. The main fan leaves of the plants are turning yellow, and curling up and down on some. even the green leaves are starting to curl down. The yellowed leaves stems and veins are a reddish purple, but not too bright.temps are fine, h2o ph is around 5.8. We wanted single colas, so we kept the girls un-pruned and 24" tall. grown in a closet w / 7 23w cfl and 2 43w cfl @ 2700k. Obviously there is a nutrient deficiency, but I dont know what it would be. What do I need to do to give her back her sexy luster? Again, sorry I do not have pics. I know they would help tremendously. I also looked at the general problems page, but I couldn't find any definitive proof. Oh yeah. I also noticed 1 single knat on one of the girls. Could this be a problem, and what can I do to combat it now before its too late if it is?

btw...... the nutes were given at 1/2 strength and this whole problem was before the nutes were given.

if the yellowing is affecting new growth it could be a sulphur deficiency. if the yellowing is happening on lower or middle leaves then it could be natural or a nitrogen deficiency.

Does it look more like bleaching/pale yellow or spotty dark yellow to brown? If it looks like bleaching then it could be sulphur - if it is darker and more spotty - i would guess nitrogen.

Of course it could be something else altogether. though i doubt a single gnat would be the problem

Nobody reading this has anything else to tell me about this problem?

i think you should use a mix of epson salt and a nitrogen mix

It sounds like a phosphorus deficeincy, along with the natural lack of nitrogen. At 36 days you could add abit of nitrogen and give it a regular dose of bloom nutes i think that would help

sounds like you need to add some nuits yellow leaves are cased by nitrogen deficiency