This plant continues to be a pain in my ass. It basically looks very similar to when this thread was started. The good thing about that is it's not getting any worse. At this point a lot of the bigger foliage is still yellow or yellowish, although many of these leaves now have dark green veins, so we'll see what happens. The smaller leaves have become much darker green and a couple are showing hints of nute burn, so I am maintaining the level of nutes now.
I've been feeding around 1.25tsp/gal Jack's 30-10-10 along with either 2tbsp/gal molasses or 5-1-1 fish emulsion at every watering (every 3-4 days). It has also received two foliar feeds with 1tbsp/gal 5-1-1 + .25tsp/gal 30-10-10. It is now getting 1.5tsp/gal Jack's 30-10-10 and will probably continue to get that until harvest unless it starts to respond differently.
Here are some pics. First shows top view of the plant. Second is side view, where you can really see how the smaller undergrowth has become a nice dark green although the bigger leaves and canopy continue to look light green and yellowish. The third pic shows the plant under the HPS with my bagseed plant. Right when I started this problem plant on nutes, I kicked up the nutes significantly on the bag seed plant as the bottom leaves were showing a hint of yellow. You can see in comparison how well this plant is doing having been fed properly since the first hint of deficiency.
And here are some pics of the mother I referred to in my last post (which is a sister clone of the problem plant in flower). Being a smaller plant in veg, this one really responded well to the increased nutes. It has been fed very similar to the plant in flower as described above.
The first pic was taken on 10/2. The second pic was taken yesterday, only 7 days later. Look at the complete change in color and all the new growth. I was going to throw this plant away but now I'm having second thoughts.
Well I got a bit long winded there so thanks to anyone who took the time to read this post. I may post results when I harvest this or if there are any major changes before then (but I don't expect there to be).