I’m having some issues with my angel fish. I have 4 angelfish. 3 medium sized and 1 smaller one. The aggression first started when I added the biggest one in. And the 3 original angels were bullying it. It died down after about a week. Now it’s ramping back up again. There all pecking at each other. I’ve tried re arranging my aquarium. My water conditions are solid. I need help