Yellowing fan leaves during flowering. common? do i cut?

[SWOLENPORES]

28 days 12/12 plenty of bud development, recently within the last week or so some of my fan leaves have turned yellow. is this normal? would i be better off cutting the real yellow leaves off and leaving the other semi yellow on? what do i do?? i have been reading alot and i have heard a Mag would do the trick, also i have seen that N will do the trick. but i could never find out if they were describing yellowing during flowering or vegative phase. if it is normal for yellowinging and dieing of some fan leaves during flowering maybe 10-15% of the leaves are turning yellow. one other thing this has mainly acurred from the middle of the plant up and down from the larger leaves first ect... but all leaves produced with the flower are very healthy and saturated in resin. my strain is cinderella 99. (soil) 4 fotter 20 fat tops 3.5 months old 400mh veg ,400hps flower. 1 topping and pruning right before flowering cycle.
thanks
swolen pores

[bonbon]

it could indicate a deficiency,overwattering,"ph"problem,add some silicon or a little nitrogen and magneseum to you're nutes,and check the "ph"levels as well....bonbon http://www.geocities.com/SunsetStrip/Amphitheatre/5796/nutrients.htm

[Tech]

10/15% of leaves dropping is not too much to get concerned about , older leaves at this stage will drop.
Magnesium or Nitrogen deficiency is unlikely if you are feeding them.
I wouldn,t be too worried at this stage.

Disco.....

[bonbon]

10/15% of leaves dropping is not too much to get concerned about , older leaves at this stage will drop.
Magnesium or Nitrogen deficiency is unlikely if you are feeding them.
I wouldn,t be too worried at this stage.

Disco.....
a plant turning yellow like that at 26days deffinitely has a defficiency(see his pic on the other thread),most fertilizers do not contain magneseum,so you've got to add it yourself....bonbon

[del...]

dying off fan leaves are normal during flowering...no worries. leave em be...

[bonbon]

its normal during later stages(about 2/3 of the way of 12-12)but not halfway into photoperiod,the plant still requires some nitrogen(in smaller amounts of course)to keep the foilage healthy to utilize light and nutrition at a maximum level,but i can be wrong....bonbon

[bonbon]

this is one of the most valuable tips i've ever gotten(courtesy of my mentor"Race Car Fan")....bonbon
http://www.simplyhydro.com/benifits_of_silicone.htm
http://www.altgarden.com/site/additives/htmldocs/pyrosol.html

[IlovePot]

Herbatologist~