system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5:Many sharks and other large fish have been kept in captivity for long periods of time but why has this not succeeded with Great White Sharks?

*thanks for all the responses! I believe I can wrap my brain around it better now.
gpt
Coming from an aquarist who works with sharks- Great White Sharks are what are called ram ventilators. This means they constantly have to keep swimming to keep water passing over their gills. Sharks have what is called a glide pattern- they have a burst of swimming, then having a gliding portion. When kept in human care, sharks need many things, including a certain shaped tank to allow for this glide pattern. If they do not have enough space or the habitat is the wrong shape, they cannot fully use their glide pattern to the greatest efficiency. If they have to cut their glide short, they use more calories swimming, and this imbalance makes them very hard to keep. Great whites have a huge special need for their glide pattern, so they are very hard to keep in human care. No one has ever kept an adult great white, but Monterey bay aquarium will collect and hold juvenile great white sharks for a few months before releasing them back. They never keep them longer than 6 months and there are a lot of rules about when  they can have them.