Hey mate, ive taught my oscar from a young age to mouth fight anyone who gets close enough, it scares the crap outta kids, funny as hell, and they colour nicely too. Another thing you can try is to pat him your oscar every now again to get him/her sweet on you, but too much and you'll mess up his/her slime coat. One thing i will talk down is making them jump for food...........................all these mad vids on youtube, oscars jumping for food the next week their on the dead fish thread astounded their O ended up on the floor...........