you could try an endlicheri an ornate would most likely be out grown and eaten but an endli or congo mabye even a large lapradei
get one atleast 12'' long bigger if possible pbass can eat some big foods and bichirs don't grow very fast lapradeis grow pretty slow so they could only work if you got a big one pver 18''
they grow to about 32" and I think they are one of the fastest growing bichirs. I don't know the exact growth rate, but I'd guess they can grow almost an inch a month.
also make sure the bichir gets its share of food. i know pbass can be very fast when it comes to feeding.
and as mentioned, generally bichirs aren't fast grower, compared to other fish like the large catfish or arowana etc. but juvy bichirs can have impressive growth!
ornate can reach 20"-24" in captivity. endlicheri also in the same range. But it will take both a good number of years before getting that big. their growth will slow dramatically when they are in the 16"-18" range.
Enchilada..... I like that just as much as I like the idea of PBass and *ha* Enchiladas in the same tank.... Enchilada! One of my Enchiladas is named Gustavo - Gustavo the Enchilada. Sounding quite Mexican instead of African, huh?