top leaves problem.

[shuggy4105]

for around the last week, the top fan leaves are yellowing/light green at the edges,but the centres remain a darker shade of green.
these fan leaves look dry, and have some "light brown spots" on them, scattered.
i had a problem earlier with over-fert,so i flushed and she has recovered well, with the exempt being this.
i`m in week 3 flower and using a 400w HPS, ph is cool, and ferting with some dilluted bonzai juice 6-4-4, they love it
the lamp bulb is quite close to the tops, like 6", but i have a fan blowing directly on top 24/7, and it doesnt feel too hot when i do the hand test.
i need the lamp close so the bottom branches get good light,as she`s 5ft.
i`ve been looking through all the trouble-shooters etc but can`t find anything to exactly match with mines.
the new growth is fine,but when it develops into a larger leaf it seems to dry and yellow slowly-with the eventual light brown spots when they are the main fan leaves. but like i said, it`s only on the top of the plant.
the other tops lower are extremely healthy.
i know a pic speaks a thousad words man, but my cam is crap-a little megapixel key chain one, i`m waiting on a USB connector for my cam-corder
as i`m writting this i`m thinking it may be a mg def:stoned: but only at the top of the plant , and i`ve also got to consider she had some burn she has recovered from, although very recent.
maybe i should give her a shot of epsom salts and see what happens.
any ideas :welcome: ostpicsworthless: for sure...

 

[THE BROTHER'S GRUNT]

Well Shuggy it sounds like two things. Either your light is burning them or they are still being burned by the nutes. Have you started her on nutes again?

 

[shuggy4105]

not yet man, although i gave maybe 1/2 pint of water containing nutes for my seedlings NPK 1.8-2.2-2.8, maybe that? it was very dilluted,around 3 days ago.

 

[THE BROTHER'S GRUNT]

Did you give any to the plant that's having the problems?

 

[shuggy4105]

yup, that`s the one i`m talking about, around 1/2 pint of very low-dilluted fert. maybe not even 1/2 pint, just the left overs,although i thought she had recovered, and was about to start her on a low dose again.
would this only affect the top?

 

[THE BROTHER'S GRUNT]

Maybe Shuggy. She might need another flush. Let's see if anyone else wants to chime in.