Hello, I know this isn't really fish but it is still a aquatic creature so I thought I would put it here. my African dwarf frog now has this "thing" on its head. It's like a little dent in his head. When I pick him up and look at it, it looks like his skin has been ripped off or something. I have a beta and another adf in the tank and they are both peaceful and never fight, the two ADF's are almost best friends. So, I don't know what this is. I have quarantined the frog in one of my old tanks but I don't know what to do, it's so weird! It wasn't there a week ago. By the way I got these frogs about 1-1.5 months ago and the betta about 3 months ago. thanks for th r help, and also I have provided some pictures below. Sorry for any miss spelling, I am typing this in my iPad. Please tell me what is up with this frog. Thanks.