Rust fungus or def

[N8tro]

Spots on lower plant leaves seemz to be spreading also on 2 seedlings 2 of my photos seem to be un effected

 

[Stooby snacks]

Filling out the form will help us get a better picture in the minds eye.
Im gonna say cal/mag deficient though.

 

[N8tro]

Turns out to be a calmag def. Added some epsome salt and it stopped spreading