I want to give some of my swordtails to my brother in law. He is not interested in breeding them and I have way too many males. Will the male swordtails be less aggressive toward each other if there are no other livebearers in the tank? I was going to give him 7 or 8 of my males which would thin down my own population to 3 mature males and about 10 mature females (and a lot of youngins).