What kind of plate is it? Long tenticle or short? Short plates have a great success rate in the home aquarium with the correct conditions ( placed on the sand bed is a must, at least 4 watts per gallon lighting, regular feedings of meaty foods) The long plate however is a whole new ball game, they do not fair well in captivity and will die for no reason in a short amount of time. They can look great one day and be dead the next.