light burn/ heavy dosage of nutz/ rot?

My setup is run on solar, and had an issue with a battery. The temp spiraled out of control,topping 36c and low air movement. This led to mites..used a few sprays but neudosan cleared that right up! buds are small considering i used a 400w de gavita..achieved more with a 100w optic xl cob light and lower power usage. all this been said, i think i over powered with nuts leading to dying leaves causing a small yield, and the factor of high temps with low air movement for a period of a week or so.. once i started to see the denaturing of the buds i cut them down. decolourisation of the buds is happening in all my grows? is that normal?