Hey I currently have a Silver arowana around 8-10 inches maybe, in a 125g tank. He has been in the tank for about 2 months now. The problem I see is that the arowana sits in the top corner of the tank all day and I only see him swim when its dark at night. I stopped turning on the light because I do not have an LED for him yet and I was afraid the lights I had were too bright for him. He is also very frightened of me and swims like crazy and rams himself into a wall and splash the surface when i move a little too fast. He is scared of everything and just likes to sit in the corner. His inactivity concerns me. Right now he is in a tank with a small pleco that likes to hide in the log decor I have and I used to have 2 1.5 inch oscars. I removed the oscars because I noticed they chased him around and at night I heard a loud splash n bang and when I went to check I saw the two oscars chasing him. I have 2 large sponge filters hooked up to an air pump that provides quite a bit of surface agitation and I have a fluval 306 with the output pointing directly down because I was afraid the output would be too strong and create too much of a current. He has started to move a little more since I pointed it downwards, but I am still concerned. Is he just not used to the tank yet? Is he stressed? Does he need tank mates?