Garage epoxy question?

I applied some 1-part epoxy garage floor sealer from quickrete on my floors today. it hasn't been 24 hours yet but i can sc some of it off with my figernails if i try. Is this a concern or should I just wait a little longer to see if it gets harder. also i got it colored and noticed there are some white clumpy stuff in the bottom of the can. what is this?