Time Out says
This straight-forwardly named Pink Lake is found right beside the Western Highway. If you’re headed towards Little Desert National Park, this is a great stopover, and you can get a good view of the lake from the rest stop on the side of the road. The brightness of the pink hue depends on how much rainfall the area has gotten – if it’s dry and there’s less rain, the concentration of pink is stronger. Fun fact: the salt in this lake is harvested by the Mount Zero Olive company.