Hello RS.

Welcome to Fish Lore!
As for feeding, Aquatic Mouse mentioned about crickets, you can get crickets at most bait and tackle shops cheap. You may have to buy the container they come in but that is a one time deal. You can reuse the container over and over. It may be $5 at the most. Compare prices with your local fish store (
LFS) Too, I'm not sure what size food sticks you are using but I've seen "Arowana Food Sticks" that are fairly good size. You may have to order them on line. Try drsfostersmith.com or thatfishplace.com. I feed them to all of my fish and they love them, even though I don't have an Arowana.
Here is a link concerning Arowana's .
http://www.fishlore.com/profiles_silver_arowana.htm
I hope that you can move him to a larger tank as he ages. They can grow to 40" and really require a much larger tank and what is suggested is 200g or more. Personally I think more. Wow! A long lifespan as well. You're looking at 10 to 20 years
I hope you enjoy the site. We love photos around here

If you ever need any help by all means let us know. Too, feel free to chime in to conversations anytime you like.
Best wishes.
Ken
