Don't put plecos with your Bichir you run the risk of them injuring the Bichir. I have no expeirence with BGK but in a tank that size with ample hiding places more than 1 should be okay. The Ornate Bichir has the potential to reach 2ft. so suddenly your tank will not look as big. These fish live in large bodies of water and find food so your tank will not be to large.