Saw Blackfish too, it's just mentally unhealthy to put such a big behemoth in a sterile fish tank basically. It's like sitting in a solitary cell for the rest of your life, mental mishaps are a sure thing to happen.
"The ultimate guide to penny pinching" on netflix is a fun one to watch; there's a guy that hasn't bought meat for years because he puts roadkill in his freezer to eat instead, and in hindsight is actually healthier than the treated rubbish we buy in the supermarket.. Check it out.