put jellyfish into a smooth bottle, filled water almost in full bottle, put jellyfish inside and press bottle, see fish dancing. 1. hydrodynamic ... but leave little space, put jellyfish into bottle, cover lid, hold the bottle and press it, see jellyfish dancing inside.3. ... down when press bottle.4. hold onto the bottle tightly, when jelly fish is in the middle of bottle, and press bottle again and ...