I got one of these today. I have a 46 gallon 7 year old mixed reef. I have about 60lbs of LR and no sand. What do these guys really eat and do I need to supplement there diet? I acclimated for over an hour to get the SG, temp the same.
Nobody really knows what they eat, but it's been hypothesized that they eat a surface film off the rocks. That being said, the odds are that you won't be able to keep the star alive long term. Most seem to die between 6-12 months after being purchased, although some last as long as 18 months (mine did, in a fully stocked 80 gallon).. The theory is that they slowly starve to death in "smaller" tanks, much like that other "reef safe" star, the sand sifter.