Small deadly fish.

When I was a small girl my father had an aquarium with fishes. He had many kind of fishes and water plants.
Fishes were living in harmony and we liked to watch them. My father fed fishes and cared about than, so that water was always clean. He liked a lot his aquarium and fishes. One day my father bought a new fish, she was small, yellow and she had three black perpendicular stripes. The new fish was very nice and very active, we had impression that she was everywhere at the same time. After few days strange things began to happen in the aquarium. Fishes had torn fins and tails. Afterwards my father began to draw out dead fishes a little too often. My father cleaned the aquarium and changed water. When fishes were in a jar the small fish became furious and began to attack all other fishes. My father quickly drew out the small killer. The small fish remained in the jar alone, but she lasted only few days.
I don't know the English name of that fish. Perhaps somebody will help me, I will be grateful.