Pretty positive its blunt force trauma… was hoping the upgrade would subside this ones freak outs. It would sit on one end of the tank and just swim into the glass crazy then up into the lid for no reason then fine for weeks.
Im still new to bichir but i dont like the random freak outs for no reason thats for sure. Short life spans with high price tags makes me not want to collect alot of em lol.
… smallest one went from 6” to 10” and the largest went from 8” to 12”… going to up them to the 500 sooner than later. 
… seems like some grow painfully slow and others rather quickly. I enjoy the fast growers of course lol