Weird behavior in my sailfin molly

Question
Two questions i have about my sailfin molly 1st is my sailfin molly is male and is showing aggression to my other fish is there a way i can help prevent this or at least ease him?
2nd question is the molly i noticed has secreted a cloudy substance from his gills but none of my other fish are and it seems he dose this when he is being aggressive to the others what can this be is he sick?

Answer
Shannon,

 If you have a fish showing aggression, the best thing to do is remove it from the tank. It is most likely stressing the other fish out. As far as the secretion, they do release ammonia and water from their gills. I do not think it is anything to worry about. Make sure he is the only male in there. If you have more than one, there is a reason he is aggressive. You didn't mention what other fish you have or how big your tank is. If you choose to keep him in the tank, just keep an eye on him so that he doesn't hurt or kill any of the other fish.