After one day at the pool the pink is almost all gone. But it was fun as long as it lasted. Viola´s hair might be a bit to dark to begin with. If you have lighter hair I think it will “stick” better.
We used Stargazers Semi -Permanent. If you have a short hair one bottle will be enough. We could have used two though.
Another cool thing we bought is a water proof case for the Iphone, called LifeProof. It lets us film underwater with sound and everything. Love it.