I worked at a retirement home for almost three years, waitressing. Halfway through I got two very visible arm tattoos done, and there was no problem. Several other people had very visible tattoos also. Also, a lot of the residents asked about it and I only received one or two negative responses as a result.
Anyway, I have since quit that job to go to school full time, and am interning at a different retirement home. I don't know their guidelines as far as tattoos but I'm keeping mine covered up just to be on the safe side. Also, I am majoring in gerontology so the chances of me having to cover up for my careers are pretty high. No biggie though.