Are you asking advice about getting a female, or do you already have her?
If you already have her, you either need to get about 5-8 more females, or take this one out immediately. She WILL get totally stressed out, by having three males trying to mate with her. This will make her more prone to diseases, and it can also make her die. Also, the males will start fighting over the female, and they may kill the weakest male. At the very least, you'll have shredded fins. Seperate the males and female NOW, until you figure out what to do. Even just putting her in a breeder net will be better then the situation she is in now.