Blue Button Jellyfish

Found near the surface, drifting in bays, estuaries and lagoons also out in the oceans, moving with the currents, tides and winds. They are often blown ashore in bad weather. The round hard float is almost flat with stinging strands of hydroid surrounding it, each strand has little branchlets off, they do not give a powerful sting, more of an irritation.
Depth - surface of the water

These are not true jelly fish they are Siphonophore a colonial organism made up of zooids.
Jellyfish are 95% water.
They have no heart, brain, blood, or gills. The body of the Jellyfish is called a bell. They do have a mouth, tentacles and arms around their mouth. They use their arms around their mouth to help sense and find food that ends up inside their mouth.