can black-tipped reef sharks...

[tidebreaker]

I'm concerned about the shark at my LFS - a black tipped reef shark in a 100 gallon tank. Do sharks need to swim and sleep simultaneously, or can they settle on the bottom to rest. It seems like a pretty small space for an active species.

[floralix]

I think all sharks have to swim constantly because their spiracles don't move, so they have to keep water flowing over them to breathe.