I had a fish like this and he had a little pineapple house like spongebob's and one day I was cleaning his tank with him in it (mistake 1) and I took out the pineapple to clean it and when I put it back in, it wouldn't go all the way down so I was shoving it into the rocks (mistake 2) then I realized that the fish had been under the pineapple the whole time and I was bonking him with his pineapple house. He died the next day.