Water beads, we have a nickname called Spongebob over there, which is about the size of granular desiccant. It's hard to dry, and it will grow bigger and bigger in the water, crystal clear and soft to the touch. The main component of this kind of thing is silica gel, which grows by absorbing water and expanding. In fact, it is like a semi-permeable membrane. You try to put salt in the water. If the concentration is too high, it will shrink and grow back in fresh water.