AusBonsai

Hey , i have a chinese elm that i have had only a few weeks. It was in a nursery pot , it seemed fine but last week quite a few leaves have gone bad ie brown and brittle and i have pulled them off. There are new shoots and buds growing but not at the same healthy rate that my other elms are shooting at this time of year . I noticed some of the leaves have these white spots on them . The spots dont rub off and only stay on the outter edge of the leaf . Any ideas ??

I don't think I have seen this before. Maybe some dreadful tropical disease

Haha fantastic man can't grow a bonsai but can create a new disease ive just sprayed it with a yates copper fungicide so hopefully that will knock it on the head