Okay... this is what happened
My Sis broke her tank down and shut off all the filters in the tank thinking the Mono could survive... I found out about it 5 days later and took him in (The Mono).
I knew with my VATF he would get beat up so I put him in my 50gl grow out. Bad move... he stressed all my fish in there, including my new B.Suchus... moved him.
Put him in my daughters corner tank... bad move. He stressed out one of her angelfish and nipped the heck out of her Discus (took 1 day).
Put him in my Sump with my grow out Armatus, Spotted Red Hooks and Fei Feing... Bad move. He was nipping on my Armatus... so in the 300 he went. I put him in on a Saturday morn (bout 2 weeks ago) so I could keep my eye on him... everything was fine. He would nip at everything in the tank except the Tiger Fish. My Congicus got it the worst (but nothing to bad)

. Everything was running smooth till yesterday, I seen the Mono dig deep down in his pants and nip at the Tiger Fish. Tiger Fish just swam away. I seen him do it 2 more times but the result was the same... ATF swam away. Woke up this morn to a Face-less Mono Sabae
This is the first casualty due to aggression with my VATF. Every tankmate in here is flawless (ATF did scrath my Kitumba 2 times a while ago but healed up perfect).
Im just tripping out on how the bite looks... it looks like one bite did it and another hard bite on top but nothing scratches.
R.I.P fin nipping Mono Sabae