European aquariest will hardly ever see this fish. It's a deep sea fish wich can be found in depth of 55 - 100m. You need special helium diving equipment to dive that deep.
The price of the fish was $5000 years ago as a result of the depth and the difficulties to catch him.
P. boylei live in smaller groups. According to Mergus this fish has succsessfully been held in captivety, however I think it should be left where it belongs - deep in the ocean.