Should I ask my daughter to not get anymore tattoos?

You need to show some loving concern for your daughter. You should have never let it get this far because now if you try to say anything, they will gang up on you. Start by talking to your wife. She needs to back you up when you say no to your daughter, and you say no to any more tattoos or piercings. Then talk to your daughter. Tell her how you feel when she comes home with another hole in her head. Tell her that you are afraid she will become a dancer. Be prepared for her to say anything back.. she is 15 after all. But the important thing is you have to open those lines of communication so your voice can be heard. Good luck to you. You're going to need it.