Ferted it with 15-30-15 (NPK)
As well as a dash of epsom salt.
No signs of improvements in 3/4 hours.
It's only the fan leaves that are going yellow right now, the bottom 2 leaves are going down the stem, yellow, and crispy.
Pretty certain they are dead, and its slowly creeping up the plant.
Except, on the nodes its not affecting the parts that are flowering.
For example, my lowest node (lower than the yellow fan leaves) is fine, but the tiny fan leaves that were growing of the side of it are yellow, dropped, and just look mashed.