I learned that no matter what the pet store people and online resources say about an animal being only Simi aggressive and it being mostly an individual trait that can not be attributed to the entire breed: That a blue crayfish can and will go out of his way to eat your favorite gold fish. And they were doing so well together, in what I though would be an adequately sized tank, until Captain Snippers killed Sergeant Wiggles. So dont take the chance and mix fish with different temperaments because Wiggles was several times larger than the crayfish, Snippers, and he was still taken out. I do miss that fish.
