anything that isnt to aggressive and fits in the tank is an option. Rope fish are so lovely.
i would go african theme you might like some of these:
-butterfly fish (1, more might kill eachother)
-african knifefish (nigri)
-ctenopoma
-congo tetra's
-smaller bichir species (same order as ropeeels)
-tire track eels
-eel catfish (some species get massive, do watch out)
