10,000 gallons is not enough still.Think 20,000-25,000 gallons.I'm not trying to flame you,as I am happy you are giving sharks your best care and they will end up in a better place with you caring for them.I just don't see the need for a blacktip. I had a blacktip at one point too. Cool to watch and have.But I had to give him away. Try to find a place that has the proper tank size,then keep him for as long as he will last in your setup.Then give him away.That's what I did at least.