Black spots on RETF

[Shaunalea15]

Hey there, I purchased my third RETF last week and when I brought him home he was mottled in color. when I did some research they said he may be just stressed or other things I found was bacterial infection where he had bright green spots. I treated him with metafix and used polysporin/neosporin and now he has black spots. Think it could be scars or is it fungal? He is eating and active so I'm hoping it just a scar. I posted a few pics, first one when I first brought him home and second one that I just took today.