Welcome!
I'm pretty sure lighting is a secondary thing for most fish. The only thing that matters is whether the fish is nocturnal or a day-swimmer. Since I'm almost certain arrowana are most active during daylight hours, any lighting that is in your tank should suit him just fine. This may not be the case if you have a strongly lighted plant setup, as this might get too warm or cause the fish vision discomfort, with it being a top-dweller. (Imagine a fish that looks "up" most of the time having to look at bright, bright light all day...)