Tetra Peeling Scales Red Eye Tetra Scales Peeling?

Red eye tetra scales peeling? - tetra peeling scales

Hello, I have a community tank with about 20 fish that is ready for about 3 months. My three red-eye tetras have problems with your skin ... on the sides of fish scales / skin appears to be deducted and are gray-white. It is also very red in the Gill area. None of my other fish seem to be affected by this problem, including my Serpa and neon. I tried to find information about the network, but can not see photos that look like Saddleback diseases, safe, "but it's something different in the future. Anyway, if anyone can suggestions about how to deal with this or where you information about something which sounds similar to find a lot to offer, I appreciate it. Thank you!