I keep a 11-12 inch BGK with my Ornates, Laps, Endli's and Sens without issue. They don't seem to bother each other. BGK is a good bichir tank mate but a very slow grower so be wary if growing out with lower jaws as he might become a tasty snack. I recently moved my sens out to a breeding tank but last night their tank just randomly cracked and water was going everywhere so had to put them back in the main tank temporarily till I get another suitable tank for them.....bgk seem to work well with upperjaw polys