I have two tanks set up... the 95 has the brittle, sandsifter and blue starfish in the tank... and the crabs I did have, 2 sallylightfooted have long disappeared.
So to answer your question no chance they will survive long.
In my 72 I have the 2 pom-poms and 2 blue porcelain crabs along with a blue and purple linkia....so they are safe.
....unless the newly discovered hairy crab gets hungry.....
