About 16 inches long so far. Hoping she doesn't get bigger, but her and the oscar will be going to the big tank in a few months anyway (its 78"x24"x24" but they don't get on with the Pacu)
It definetly rules out senegal since she's 16 inches. Senegals usually max out at 12". She'll probably grow more since yours looks like it's a member of the lower jaw species. The bichirs in this category typically ranges from 24" to 36". Her growth is probably slowing down though so you'll have time before having to move her to the big tank.