I have a 29 gal i wouldnt have anymore fish if i was you considering you have some potentially large fish there they will easily grow out of a tank that size m8
Maybe if you took some fish back you could keep a couple of these LINK couldnt keep any mbuna or malawi species though
Also the silvertip sharks sound like the colombian shark catfish which not only grows too big for your tank but also needs to be moved into brackish water as it grows