Sounds like quite the undertaking. The more I read about sharks and see them I think I am of the opinion that sharks may not really belong in the home aquarium trade. I do enjoy them in public aquariums. Because of size many inexperienced end up buying juvenals from less less than reputable LFS
willing to sell them without educating people on the long term care requirements.
I am not saying this to squash your ambition as it seems you are at least checking it out before jumping in. I have just seen them a few times at two LFS
I frequent and in all cases they are basically rescues where the originally owner ran out of room or became bored with it. In fact one LFS
has a 4000g tank with 2 nurse and a bamboo that they took in years ago. The nurse sharks are close to 6 feet. For the LFS
they are a novelty and draw people in and I think the tank which is basically a concrete block structure under all the display tanks serves as a large sump.
It just seems to me there is a lot you could do with a 220g tank other than house one animal that may require larger accommodations anyway . Just a thought.