question for the pro's

a few questions i'd like to ask y'all before i start drawing up my designs for my personal tattoos i'm about to get in several weeks: 1) about how common is it that people get allergic reactions to red? and, 2) what colors look best on darker skin? my skin tone is pretty much medium ( think of a very tanned person's skin), i also get darker when i go to the beach a lot, especially in the hot summer...i want to know what colors you guys think look better (since i know there are experienced artists here) so i can just use those color options in my design now, i want to just have my artwork ready for the artist to put the needle to my skin without changing or adding too much. i've heard varying accounts on what colors pop out on darker skin. thanks in advance