Hi everyone I have 4 platy (3 female, 1 male) in a 15 gallon tank. I used to have 2 males but the smaller male was chasing the bigger one and harassing one of the females so i rehomed him. Now my remaining male is acting strange. When there were 2 males he didnt pay attention to the females at all but now i think he's biting the female my last male was harassing. He flattens all his fins and tail and darts at her and bites (or it looks like he bites) She doesnt seem all that bothered by it as there are lots of places for her to hide but she doesnt. I am currently cycling my quarantine tank and i am considering putting him in it as i am worried about the female as she is starting to look a bit pale and i think she is pregnant. I am considering using my quaranting tank as his permanant home. I have checked her fins and they are all fine, no rips or anything. Also he only pays attention to her and she is the same colour as him (orange and black), my other 2 females are yellow and black. I dont know if this matters. If i did use my quarantine tank (10 gallon) as his permanant home i'd be scared to add more fish to it (of course once its cycled) incase he was agressive towards them. Not that there is much more i could fit in a 10 gallon. What does everyone think? Will he calm down or should i move him?