Well arowana are top dwelling fish so that's normal for him to be at the very top. Wat size tank filter and what's ur water chemistry? Usual aros are shy for couple days or weeks to there new homes and they will not eat. If ur water chemistry is good then just keep tring and he will com to they always do.
he's on 180gal by himself with eheim 2217 and 2 AC110...yeah i know aro's are top dwellers but this one is not normal.. he just stay on one place, he was eating and swims normal in last 3 days but when i did WC yesterday thats what happened...