For sure get it out of there!!!!!!!!! I have a 22 inch Black Aro and I introduced an 8-10 inch Ali-Gar in with him and in about a week after the Gar settled in real well I arrived home from work to my astonishment saw teeth scrapes on the upper rear back and torn tailfin and cadual fin of my Aro. Needless to say that gar was instantly ( no joke ) removed from the tank and traded in for a TSN of about 4 inches. Cool fish but I find it too nasty for Aro's. J.M.O.
Mike