I have a Hi Fin Platy that has nipped a huge bite out of my plump zebra danio's tail fins. The chasing seems to be almost constant now. I used to have 2 zebra danios, but one died of a gill flukes. What can I do to quell the Platy's aggression before its too late. He has always chased but not this much. There are many other fish in this tank, including another platy, and plenty of hiding spots, but the zebra danio doesn't seem to understand that he needs to hide! Please help!