Crocea tend to be an easier clam to keep (easy is a relative term when it comes to clams) They don't get as big either which is preferable in a smaller tank.
They require pretty good water params and good lighting but with 250 you have more than enough IMO.
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- Greg
90G : Light - Tek 6xT5 | Skim - EuroReef RS135 | Flow - 2xVortech MP40W | Control - Reef Keeper 2
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