Hey /an, I have a question.You see, I got a fish from my sister over a year ago, she didn't want it anymore because it was pretty territorial and killed her fish.Now the thing is it's pretty lazy, all it does it float in corner, and swim over to get food when I drop it in.Is this normal for a fish? He's getting pretty old I'd say, though I know nothing about fish. I have a filter and a "airartor" in (It used to push out many small bubbles, but since that thing got moldy, I had to throw it out. Now the tube shoots out larger bubbles).So is his laziness part of old age, or my fault for doing something wrong?Pic unrelated
put a cheap small fish in it and see if your old monster tries to kill it again.