I added another picture that shows leaves better.
Every cutting is from same mother except one and they all get exact same nutrient mix.
Maybe there's a air pocket in root ball or roots are getting restricted.
I may try giving the one pheno a bit more N or feed it an extra time in light cycle.
Since other cuttings look great on same diet it makes it more difficult to pin point problem.
Light source is very uniform and since plant is now in same place as other healthy ones were,I don't think it's light issue unless it's getting too much.
The system I use produces 1100 pffd which may be too much.