Blue dye or pink dye?

Sarah • Mom of 2 (ages 14&11). TTC #3 since Jan 2014 with new hubby (his first). #1 miscarriage November 2015 :(
Ive seen so many comments out there about horrible evap lines but I can't remember which was the fav - pink? Or blue?
​What's your "go to" brand/color dye and why?