Grr...when I went to feed my fish I noticed Koi's tail looking different. I think he is biting as it doesn't look ripped, and no sign of rot.
A little backround I do approx 2 water changes a week 1 with a vaccume the other I just cup the water out. He is in a filtered 10g with two tank mates. On one side of the divider is a male, on the other side of him is a female.
He has plenty of flare time, and really loves the bridge. He has 3 plants two silk and 1 plastic. He has been in the tank over a month. His tank mate approx the same time a week or so difference between all.
His is the middle.
So what can I do to try and stop this before it gets worse? Is he maybe to stressed out by his tank mates? They didn't seem to bother him before. Could he be bored? The only change I can think of is me spending less time in my room then before. Otherwise no changes.