For two years now I have kept three freshwater flounders (Achirus achirus) together. They came in at about a quarter size and now the largest is 2 1/2 inches, big enough to share in the trout worms I feed my larger fish.
Shortly after the flounders reached 2 inches in size one became aggressive toward the other two. I first noticed the smallest flounder had a chunk removed from its side. I figured larger tank mates were to blame, so I put the founders into their own tank.
One week after this the smallest flounder was dead, with several chunks missing from it's body. Now I knew this was not larger tank mate aggression, but instead another flounder. This was really weird to me because I've never read anything about these flounders being aggressive.
The next week the next smallest flounder was showing the same missing chunks. It was later that night I observed the largest flounder attacking the smaller flounder!
The larger flounder was taking bites of the smaller one, and even took off an eye!
I separated the two flounders, but it was too late to save the bullied one.
These fish were totally peaceful with one another until the two inch mark. Maybe the flounders reached sexual maturity and that caused the aggression.
Has anyone else experienced aggression with freshwater flounders?
Shortly after the flounders reached 2 inches in size one became aggressive toward the other two. I first noticed the smallest flounder had a chunk removed from its side. I figured larger tank mates were to blame, so I put the founders into their own tank.
One week after this the smallest flounder was dead, with several chunks missing from it's body. Now I knew this was not larger tank mate aggression, but instead another flounder. This was really weird to me because I've never read anything about these flounders being aggressive.
The next week the next smallest flounder was showing the same missing chunks. It was later that night I observed the largest flounder attacking the smaller flounder!
The larger flounder was taking bites of the smaller one, and even took off an eye!I separated the two flounders, but it was too late to save the bullied one.
These fish were totally peaceful with one another until the two inch mark. Maybe the flounders reached sexual maturity and that caused the aggression.
Has anyone else experienced aggression with freshwater flounders?
