I understand, I would have jumped too at FREE lol! But yeah, next time take a deep breath and think about it.
Srorities can be difficult.. The females basically have to learn to live together and tolerate each other. If you do get a sorority going, make sure you have extra tanks for girls that just wont get along. Also get a breeder net to time out ones that are getting picked on or are picking on the others... If you get sisters that would be best because they're more tolerant of each other... I have a sorority with 5 girls and 4 platies (I call them the intervention fish) in a 20 gallon. Sometimes if two girls bicker and a platy passes by they stop to look and forget what they were doing lol! If you need any help we're always here! And good to hear that you're gonna research and not jump into it like a lot of people. :D