It is absolutely positively an exception, please believe me
It is really important to note that it is VERY rare to get this to happen, this is not common, nor can it be assumed it will.
The overwhelming majority of these stars will not live anywhere near that long in our tanks. The overwhelming majority die of acclimation shock or starvation in smaller tanks.
How big is your star? There is a blue morph of the much smaller Linckia multiflora that might very well do fine in that type of sytem.