I'm personally not sure, as I've never personally heard of them breeding in a tank. I think someone else said in the last thread that a member here had bred them in a tank. I tried using the search function here on MFK and couldn't find any posts or threads about Arowana's breeding in tanks though as I searched after hearing it. Still I'd think a 450 would be too small. As it is they like to choose their own mates so just sticking a male and female together doesn't necessarily work. Usually they're kept in a school of 6 minimum till 2 pair off. That's primarily why it's unheard of or virtually unheard of them breeding in a tank. Plus much like poly's they have to be fairly close to full grown to breed. It's why poly's as well aren't bred as often as cichlids as it can take quite awhile for them to reach sexual maturity. At least what I said is true as far as I know, I never give definitive's as I never know perhaps I've missed something in my research.