Hello, I’m new to saltwater aquariums and the first two fish I got were clownfish. I’ve had them for about 3 weeks now and they always got along fine until three days ago when I did a 4 gallon water change on my 40 gallon aquarium. During the water change I also took out the pump, heater, and protein skimmer to clean since they were getting covered in some algae. The next day I noticed one of the clownfish hiding in the corner behind the protein skimmer and the other kinda keeping it there like he had him cornered. He also seemed scared to eat. As the days go by I notice they’re almost back to their normal ways except I still see one attacking the other sometimes and I have to drop food on opposite sides of the tank or the mean one won’t let the other eat. I know it’s normal that one will try to assert dominance but the other ones fins are getting damaged. I’m also wondering if I stressed one out so much during the last water change and that’s why he started being aggressive or was it just a coincidence that they just now started trying to assert dominance?