What could cause the yellow edges on the growth of new leaves that’s affecting only 1 plant. Soil of this plant also seems to be more moist than the others but all are bottom fed via autopots.
Your ec needs to be at 1.4 to 1.6 your ph needs to be 6.0 to 6.5, 6.3 best for flower. Check your runoff ph and ec levels and get them in the proper levels and things will get better. Old damaged leaves will not improve. Cheers