I found this online about your star...
The Bali Red Star is a miniature star fish which stays small never exceeding about 3 inches. Found over sandy substrates, on rocks, and sometimes climbing among corals and other invertebrates, they are constantly foraging for micro-organisms and detritus to eat, so the aquarium should have ample amounts of live rock. Red Bali Sea Star is very intolerant of sudden changes in temperature, oxygen levels, salinity and pH of the water, and cannot tolerate copper-based medications.
Also stated that the tank would have to be very matured- as in over a year old.