I'm sorry to hear that about ariel. I know you didn't mean to let it happen though. I thought all female bettas got along too. I use to have one female betta and I put her in with my male betta thinking they would get along! A few hours later I came back to check in on them and he had bitten her all over! I later found out you shouldn't put a male in with just one girl. She lived and got ok though. Her name was Scarlet. I had her for several years.