Axolotl tail is cut

[Manxolotl22]

So I’ve had my axolotls for a while now and the white one has cuts on its tail. Not sure what they’re from. They have a hide and are fed well (night crawlers and leeches mostly). There are two aquarium plants in there (fake). Not sure how this happened. I haven’t seen them nibble or attack one another. They actually enjoy lounging on each other. Any help would be appreciated. On an unrelated note, is she too skinny or look healthy? The foggy parts aren’t dirt or anything. It’s just an old tank.

 

[Murk]

She could have gotten spooked and hurt herself on the hides. The tank mate could also have taken a bite.

Just because they're usually friendly and relaxed doesn't mean they can't freak out every now and then. Even more, biting is a reflex. They can't help it - when something is moving erratically and slowly close to their mouths, they bite, even if it's a tank mate they're used to.
Usually, adult axolotls are strong and quick enough not to get hurt too badly from a tank mate biting.

This one seems slightly injured on multiple spots, so I'd put my money on it being from the decoration. She might have gotten spooked (for whatever silly reason) and trashed around the decorations.

If it doesn't happen too often, she'll be fine.