Actually...ALL of my bichir tanks are planted tanks and the only problem I've ever had is with plants being uprooted by the bichirs prowling around. I definitely agree with using Anubias species but I've also had great success using various species of Aponogeton (like A. boivinianus, A. crispus and A. ulvaceus), and Bolbitis (an African fern). If you're not married to African plants then almost anything will work. My bichir grow-out tanks are packed with Water Sprite (Ceratopteris thalictroides) which will quickly take over a ten gallon tank and completely cover the surface (if you let it). A nice, thick bed of Giant Vallisneria planted along the back of the tank makes a great green curtain and the bichirs seem to enjoy wandering through the jungle it eventually makes.
-Joe