I got a kuhli loach a week ago, which squeezed its way into the filter. When it happened the filter made a really strange noise, like it stopped momentarily, and I looked at my tank, but it looked normal. I didn't think the kuhli loach could physically get in the filter, but I looked in it later when I still couldn't find him. I overturned his favorite hiding place, a cave and he wasn't there on the second day since his absence, so I looked in the filter again and this time I saw him. When I put him back in the tank, I noticed that the kuhli loach had a white slash that is about 3/4 of an inch long on top of his body along with a few other white marks on his sides. Then, I got another kuhli loach to keep him company as well as a peacock eel. After that I noticed ich on other fish in the tank. Is it possible that the kuhli loach that got stuck inside the filter got sick from staying there? Are the white marks from having skin scraped off while in the filter or some sort of infection? It doesn't look like ich on the first kuhli, and I suspect that the ich came from the new kuhli or peacock eel. Opinions? Sorry if this post is confusing.
I'm sure that the kuhli will stay away from the filter. I still cannot fathom how he crammed his body into the thin slits, which really are smaller than his body is wide, but he won't get back in there again. His scrapes don't appear to be infected, but I'll be sure to watch for that.