Hello! First of all let me clarify a little bit. English is not my native language, it's my first time posting here and it took me a while to find the proper (if that is) section to post such a help cry. So I'm a proud owner of 4 calm fish. Two of the catfish family, two types of goldfish. My smallest one, Mituna, a black telescope goldfish had his scales damaged. To be specific it looks like he has a broken anal fin, left pelvic fin and left pectoral fin. -> No one else in the tank has ever demonstrated any kind of aggression especially not to him so I am positive it's not fin nipping. He usually calmly swims near the top corners but lately he has been laying near the bottom and very close to the filter. I've been worried he might've got his fins damaged physically because I haven't detected any signs of fin rot. My other fish also behave normally and haven't ever been sick. I'm changing the water regularly and feeding them a small dose twice a day. There is a lightning cycle I'm keeping so they wont get too tired by the light. I change the water oft-times enough and I don't keep any dangerous equipment or any plants. The only thing that got me worried is the actual filter. I've got an aquael filter. His feeding habits remain the same and he's as social as ever. I've had a fin problem before with one angelfish but it wasn't serious and he "grew" it back and it looked as fine as ever. But as of the past month its only been getting worse and I am not very patient when it comes to the health of my pets. Any help? Should I worry? Thank you for reading! EDIT: Phasing.