4th week flower, allot of yellowing

my girls been flowering for 4 weeks now and shes yellowing like crazy,im giving her tiger bloom and big bloom nutes every other feeding....wats wrong guys..is this nitrogen deficiency...please help ..rep for feedbak

there are slo brown spots on some of the yellow leaves

yep certainly looks like nitrogen to me, duno if you going to pull that back

brown spots could also indicate magnesium def

the more yellow your plant gets the less ppm's it can handle.. iv had the same probs @ about week 5 in flower and i burnt them the next time i feed them so just take it easy..lol i did foliar feed 1 plant and it did 1/2 way green up but as far along our crops are im scared of the bad things like taste and mold it could cause so i just did 1 this round
good luck and up the N next round.. it will still be great smoke just let it go as long as possible it will be fine

yea next feeding im gonna use a 20-30-20 nute...hopefully this helps stop the spreading..also the stems are purple, is this a sign of something??
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