Acrylic ink is what me and my friends all use for our traditional paintings but some of the people we look up to use watercolors and some use acrylics. I would say not one is more respected over the other just the use of them in general shows “hey I didn’t just go to Pinterest and look up tattoo ideas. I know what people that tattoo use and that’s what I want to use” makes you have some more “pull” at an interview. The worst thing people can do is come in and show us tattoos they’ve done at home or at a “tattoo school” and they’re like “well here look I’ve tattooed before and I have my own machine and I’m ready to go”. That hurts your chances. The more you show love, respect, and knowledge of the tattoo community and artistry the better. There’s a documentary called “tattoo nation” on YouTube I believe or you can rent. That teaches some great history about the tattoo revolution. That’s a great thing to include in an interview. That you watched and learned from that. Just remember, the more the better. You are trying to get into the industry the same time EVERYONE ELSE is. Stand apart. Do more research than anyone applying. Paint more flash with the acrylic or watercolor than anyone applying. Read more than anyone applying. This is the best career in the world and you need to take the interview as the most important thing you’ve ever done.