Materials Needed:

  • Cups
  • Sand
  • Gypsum products
  • Straws or sticks
  • Stainless steel mesh(size > 120mesh)


  1. Add a layer of sand to the bottom, this will be the water reservoir.
  2. Place something like a water bottle's cap in the middle, it should rise up a few millimeter above the sand.
  3. Place the mesh and a piece of clay(or dirt or wet sand or something similar) on top of the raised platform.
  4. Pour the gypsum mix, I used 1 part sand 1 part hydrostone and a tiny amount of iron oxide. Let the gypsum cover mesh only, do not let it completely cover the piece of clay(or dirt or wet sand or something similar). Dump another layer of sand right after pouring the gypsum if you want it to have a sandy texture.
  5. Stick the straw into the sand, if you want stalactite you can poke a hole.

  6. Pour another layer.

  7. Wait a few hours and pull the straw out, it should lift up the first layer too. You can take out the remaining two layers by flip the cup over and smash it at the bottom.
  8. Wash the pieces and drop them into a new cup.

  9. Now it's done! add a layer of barrier and dump ants in.