The best practice I have across the board is feeding in one side always. They learn quickly where food is coming from. Just keep in mind that they know where food arrives. Retics are very intelligent and have great eyesight and can track prey easily and move to where they see it regardless of where it is coming from. I can reach my hands in most days after tapping them in other places with little to no challenge on the rest of the cage. Feeding side takes a little more convincing that food is not coming.