Athosanswered grow question 6 years ago Your pH is fine and your overall plant health looks fine to me. Keep in mind a few things.
First, older leaves dying is quite normal, since they are mostly shaded and receive very little light, yellowing and wilting of older leaves is normal.
Second, keep in mind that some strains, when the harvest time approaches, begin to consume it's own stores of nutrients no mater how much you feed them, you should be 2 or 3 weeks form harvest. You might want to give them 1 last feed and after that only water and let the plant consume whatever is left on the soil and it's stores for a smooth smoke.
Peace and good luck, everything will be fine