I know nothing about them, but Jewel Cichlids maybe. They are African (I think).
A 48”x18”x18” tank gives options for different species of bichir. If you want to take that root, a Delhezi would be easy to find, and you could try some other top water fish. African butterflies are one fish that fascinates me. You can feed it crickets.
African predators:
-Leopard Ctenopama
-Hingemouths
-Peters Elephant Nose Fish
-Brown Knifefish
I didn’t quarantine any fish, but I don’t want to jinx myself. I bought fish from MFK members and stores with good reputations.
Jewel plus his current angel will put the angel at high risk for getting beat up.