Sharks need a lot of requirements out of tanks that most can't provide.
They need tanks at least the width of them ( for bottom dwellers) and twice the length
Once you get into smoothies and other sharks that are more active they need at least an extra foot of width to body length and 3x the length of the tank.
Vitamins and idione need to be added to tank and food otherwise your shark or ray will die of disease quickly.
A 220 is a great size for a breeding pair of coral sharks or marble sharks.
Smooth hounds can get to 48 inches and should not be kept unless your have at least a 1500+ or perfect foot print.
I suggest you get something that you can actually enjoy and keep, and not kill in the process.
While many sharks can live in smaller tanks it is much more benificial for them to have a large tank to begin with
Smooth hounds are known for running into the walls of the aquarium and messing up their face, leading to stressing and death
Even though the shark can physically fit in the tank, doesn't mean it is healthy for it to be in there.
Also i suggest cortez, round, or yellow stingrays for your tank as blue spots usually die even in expert care
They just do not fair well in captivity
You could breed a pair of catsharks ( marble or coral) or breed some cortez stingrays in your 220
Or intermix the two and still have a stunning tank and the animals will thrive for years, maybe even reproducing for you
ALSO leopards are not smooth hounds and should not be kept with other sharks. They should be with other cool water species, and I hope you understand your killing that leopard shark with such a bad temperature for it. It is written all over the web... They do very poorly over 70F in an aquarium. They need a chiller which most cannot afford for such volume of water so instead they kill the animal slowly in a tank they "think" is suitable and working. While the horn does best 68 and above. BUT most horn sharks are now captive bred and acclimated to 72-78 and thrive there. Your black tip needs 70 or above and would thrive in the high 70's.