Yellowing Master Kush leaves after 5 weeks flowering

any help would be awesome. nute deficiency maybe? light burn? nute burn?

id say a bit of heatstress. just hope it dont get worse as going buy your plants they are budding just nice. if the plants are grown in soil make sure the PH is around 7.0
put a extra fan on them and carry on doing what your doing cause their budding just nice.

ph for soil should be 6.5, i would just water with a micronute nutrient like sensical MG bloom by AN, use that 4 days after regular NPK watering

sorry im an idiot and didnt specify im using 5 gallon bucket dwc. using the organic hydroguard line: bloom/kharma/sweet with pH 5.7.
i bought a hood for my 400w hps but havent hooked it, or the ducting up yet. one of my friends said phosphorus deficiency? im gonna add a little P, and hook the hood up and see if it still looks bad. i dont want burnt heat stressed nuggets.

I think it might be a P def.Some deficiency during flowering is normal, but too much shouldn't be tolerated.Red petioles and stems are a normal, genetic characteristic for many varieties, plus it can also be a co-symptom of N, K, and Mg-deficiencies, so red stems are not a foolproof sign of P-deficiency. It seems like the fan leaves are evenly yellow at the edges all away around the plant.If it was heat they would be worse at the tops.I would add a P K supplement if you had it.Either then that the plant or plants look great....

yellowing of leaves is normal, as to N isn't taken up by the roots as much and the plants uses its stored N

your plants look great, if anything i would just use PK booster along with carbs bacteria and fungus....that should get you fat fat buds, they alraedy look awesome