To many nutes or to little?

[Bomb]

Strain: Blue mystic

Soil: Fox Farms Ocean forest 50/50 with perlite

Started grow: 48 days ago/ 30 days into flower

Lighting: 2x 100w advanced LED diamond series ballasts (3w/1chip diodes)

Temps: 70-75 at night 80-85 during lights on ( LED box's have to be run a little warmer then HID or CFL box's due to lack of light heat)

PH of runoff- 6.5

Nutes: Fox farms grow big/ fox farms big bloow fed once a week 1/2 strength of grow big/ full strength big bloom

They're two plants in a 20 gallon tub with a separator in it both are 30 days into flower and the fan leaves just started to yellow and get necrotic spots on them about 4 days ago it seems to be getting worse the yellowing begins at the tips then works it way to the veins then necrotic spots appear, some leaves get burns on the edges then begin to yellow

Im thinking maybe they're underfed? but i'd like to be sure they're not burned before i feed them more.

Ignore the little dixie cup clones around the the big budding plants, they're blue mystic clones little experiment of mine lol, and the big plant on the right is my beautiful sour diesel clone in all her glory she hasnt lost one leaf since rooting been in flower for one week now.

This is my grow box

 

[xengrow]

Looks like phosphorus maybe magnesium def and the curling looks like over watering. Need different picks of leaves. Also its hormone for the plant to pull excess mutes from the leaves for bud production. But that's more yellowing not the brown necrosis
. Your also only 4 weeks into flowering so the plant sucking nutes Would be closer to the end of flowering.

 

[Bomb]

More leaf photos

I noticed the leaflets on the buds are becoming purple now as well