Small Minstral Brittle Starfish. Help?

[Daniel.DWUW]

I'm going to be getting a 90l tank soon and was wondering if anyone has any information on Small Minstral Brittle Starfish.
I cant find any information on them at all, how big do they get? Is my tank to small?

 

[Sugar Magnolia]

I kept one in a 30 gallon tank for a few years. It was mainly nocturnal so I'd only see it for a few minutes after the light came on. I fed it sinking invert pellets a few times a week.