I am using the booster set from Robert and have come into this problem, (se pic). I did move this plant from a t5 f/s light to a led, so not sure if this is a contributing factor, Any comments would be appreciated
It really looks like Boron to me.
I looked it up in My Guide On Sick Plants and boy it sure looks like Boron
Item trying to get my lab top running when I do I will post it for you with a pick
It could be boron.
What is the pH and the EC/TDS?