About 2 years ago I had a WH RTG. I grew it for about 6 months before I decided to introduce a tankmate (the aro was only about 5 inches when purchased). I decided to add a 4" tigrinus ($500 Cad!!!) to the tank. 5 minutes after I dropped that little bugger into the tank it had dissapeared and the arowana had a suspiciously large bulge in its stomache. I knew what happened and it was too late I just had to grin and bear it. The next morning I woke up to my wife screaming "where did our fish go?". Thinking that she was talking about the tig I walk out into the livingroom when I noticed there were NO fish in the tank. After an intensive search of the apartment, I found the aro ($850 Cad) chewed to pieces in a corner. That's my story hope you enjoy it