Powder Blue Injury?

[lakai]

I can't find anything diseases or parasites that resemble this so I'm thinking its an injury? I dosed the tank with erythromycin for the time being. Anyone have an idea what this is?

 

[T_BONE]

Did this develop after you purchased him or was he like this when you got him? Does it seem to be getting worse or better?

 

[lakai]

Did this develop after you purchased him or was he like this when you got him? Does it seem to be getting worse or better?

It just perfectly fine when I went to bed and noticed this in the morning. I did a water change before going to bed so Its very possible it freaked out and started darting around. I've had it for over 6 months and it has been perfectly fine until this.