Clown Loach - Mouth looks really red?

  • We are currently upgrading MFK. thanks! -neo
Any sign of damage on any other fish? If there is they could have mixed it up. If not I wonder if you fed him something new? Or finally, could he have injured himself on décor in the tank? I would keep a close eye to see if it changes size or color the act accordingly.
 
Nice loaches. I would do more waterchanges since you can not medicate the tank. Some use seachem is it pimafix melafix? For injuries? I have a uv on standby which I turn on if I have a quarantine problem. Send a picture of your parts of your tank. They may see something in the decor. Maybe a squabble among the pack
 
Looks like you're using sand, so that's one potential source eliminated. Mine have shown irritation on rough substrate in the past.

Do they feed on mts? The rough shells can sometimes cause irritation.

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