week 6 flower think I have issues

First harvest.

Think I have some issues. I know they begin to yellow late in flower but im only on day 36.

Using a mix of floragrow and florabloom
Promix soil
2 1/2 gallon pot
75 degrees lights on
67 degrees lights off
Was using 2 400w hps, now under 1 1000w hps
Ph the water going in to 6.0-6.3

think you got a issue, its seems like you let it go pretty fare, my best guess based on the info, is a too low PH in your soil and a lock out of N and Mg in your small pots

and your water going in is also on the low side, 6,5-6,8 is more like it in soil, not much to do but learn from it, next run use bigger pot`s maybe, Im sure a repot in to a 5 gallon pot before 12/12 would have worked wonders

when you say you use floragrow and bloom, Im wondering if you also have the micro ? seems like that is missing, I use GH flora duo, but I skipped the grow and replaced with the micro using the Luca formula

http://lucasformula.com

I am missing micro, I only learned 4 days ago I was misfeeding all my plants. This is the furthest along out of my 9 plants, it was getting zero nitrogen until 5 days ago, so im hoping maybe it can recover a littke before harvest..

My question is though, is this plant still ok? Or is it unusable yield? If usable will it just be low in thc, bad taste... im deff a newbie

of course you harvest it, and Im sure it will be strong enough, quality rarely get effected, but your yield wont be the same, sure try to add a bit of micro and see if you can correct it on some of the other girls, but be careful, now would normally be the time you cut back on nitrogen