Fromia Magnifica died

[Delphinus]

As mentioned, they're -incredibly- sensitive to changes in salinity, it's usually recommended they be drip acclimated over a period of several hours, even as much as 12 to 24 hours I think I've seen recommended.

But the other problem with non-predatory stars is that it just seems to be a complete crapshoot as to what they actually eat. Either they will find something to subsist on in your tank, or they will eventually starve and die. The success rate seems to be rather poor unfortunately, for every one that "makes" it, there must be ten that don't. (I don't know the actual statistics, but that's what I've heard. Unfortunately my own experience with stars seems to be consistent with that claim.)

It seems to me the only way to pad the odds in your favour is to put them into a large system with fair amount of rock, and hope that there's enough biodiversity in the system that there's something they can adapt to. But even then ..... obviously not a guarantee.