I've had Fasciolaria tulipa in my aquarium from the egg to 4 years old. They eat each other as soon as they hatch out of the egg. They will kill and eat almost any other shell, but they don't seem to harm Cowries. They will eat their own kind until there is only one shell left. I gave up my aquarium quite a few years ago after my Cypraea arabica died.
Bob Lipe
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