How big is your tank? I only ask because when I had my blk aro in a QT (a lot smaller than his usual 240G) he was extremely skittish.
I think the larger the tank, the less chance of it freaking out.
in my experience juvies are the ones that are more skittish. as they grow they tend to become more at ease.
I have a 15" black arowana, it is still shy but when it is hungry and I wave my hand in front of it, it will jump for it. its in a 125 gallon. black/blues are usually a lot more shy than silvers. but i think that the jardini is the most fun because they are not shy like silvers and blacks and will for most of the time chase me around the tank. they also have a bigger appetite.
Hey there my silver isn't skittish at all! He only jumps when he is frightened like when I wipe the glass of my tank which shakes the tank a lot... And there was one time he almost jumped out the tank for food...