I have a predator growout right now its my 5-6inch armatus.two 5.5" goonch cats and a 8-9" endli bichir. I noticed a chunk out of the bottom part of my armatus rear tail fin gone the other day.like bit. Last night i turned lights out and watched the goonch seem to stay in place in front of powerheard but bichir moves around.and i saw him in the area of the armatus.today i notice his fins alittle more frayed. Could it be the bichir?