That setup ios in the right direction. I'd make it bigger,(20 or 29 gallong,) so you can add one of those fluval or duetto internal canister filters...makes things nice and shiny...and add a mangrove tree, they're easy and fun to grow. And if you add a freshwater bowl, you can also keep hermit crabs in there with them successfully. In fat, the hermits benefit from the salt water/brakish environment, they need low doses of salt, which is a main reason they die in captivity where they only have fresh water.