Heaters are covered . Yes there is a suspect fish ( red tail shark ) although never observed he's the only one who could . Shark is now separated offit looks as if the skin is about to shed off. Is there any exposed heater? I haven't seen anything like this except when a heater has been exposed. Are there any plecos or other fish that might be picking on it?
Thanks . Using the search function on here to see if I can find anythingMy guess would be maybe the ray caught something from one of the fish or one of the fish is picking on it. I would just try and search the web for any ray diseases. Might be a bacterial or fungus. I'm kinda of new to the hobby but I hope this will push you in the right direction
Will do . Thanks for the advicegoodluck. If you find anything post it here so you can help others in the future who find themselves in your shoes