roots roots roots...

[yogi dc]

This is my first time going dro, so can someone tell me what may be wrong with these roots.
any help would be great. its is kind hard to see but the root i am talking about are the little brown ones that are dying
the ph is fine its at 6.0
I am using schultz 10-15-10
the micro nutrents are, 1.6% ammoniacal nitrogen ,
0.2%nitrate nitrogen ,
8.2% urea nitrogen,
phosphate (p2o5)15%,
souluble potash(k20) 10%,
.0.10 iron,
0.10% chelated iron,
manganesse 0.5%, chelated .05%
zinc 0.5%.
i am also using a root stimulator 4-10-3
i have trhe right nute for flowering a will use what i used last time DNA AB