They do produce amazing bolts of blue across their mantle. They also carry parasetic crabs called Peacrabs. The last one i had held one of these crabs in it. The crab fed so much fro it that the scalop eventually died and thus left the crab with no home. This worried me because they can just as easily live within clams too so it was sumped... but without a host it sadly died eventually.
They also need very stable water and simply just dont do well in captivity. They are lovely to watch but i wont be trying them again