Aggressive platy fish one masculine one womanly?

i have 2 platy fish and one is a chick the other a dude, the chick platy is a red wag and the male is a gold twinbar, but the feminine is bigger than the male im guessing age, and she keeps biting him and chasing him around, and he just hide...is this normal for platys??
Answers:    You need another chick to spread the aggression. When he gets elder and larger he will do the dude thing and she will be the one running for cover.

Live bearers do best in groups and the ratio is two females to one manly, so he doesn't harass the chick to death with his dudelyness:o)
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