signs of illness?

Hello, it could be a calcium deffiency but its hard to say for me because if it is then early stage. It also could be normal or some water that was on the leafs. Have other leafs the same problem too?

It could be nothing, like just a little water spilt on a leaf that's caused a little bleaching there. It could be the beginning of leaf septoria, which is also related to moisture on leaves but is fungal. Can usually see a little black spot in the center of the circle. www.growweedeasy.com/cannabis-plant-problems/yellow-leaf-spot-leaf-septoria