Its yellow-brown bell, which has white or pale streaks and spots, pulsates to run water through its arms for respiration and to gather food.

Cassiopea andromeda is carnivorous and eats small animals from the sea or just pieces of them after it paralyzes its prey with its mucus and nematocysts when they are released.

This jellyfish also lives in a symbiotic relationship with photosynthetic dinoflagellate algae, the zooxanthellae, and with shrimps.

The zooxanthellae live in the tissues of the ventral surface of its body and it is the responsible for the color of it.

As the zooxanthellae gets food for the Cassiopea andromeda, in response, it gets the sunlight that is necessary for the photosynthetic dinoflagellate algae.