Has anyone used waterbeads for their centerpieces or any other type of decoration? I was originally suppose to have water in the bowls that I'm using with my center pieces but because of timing issues I can't so I will be using waterbeads. Does anyone know how long these take to soak up the water? I was thinking about doing them the night before but I'm unsure. How long do they last in the container you buy them in before they go bad?