Give him some time to eat he might not eat right away if he is a hatchling. I just got a hatchling painted like a weak ago and I put some romaine lettuce in the tank he started eating it right away. Now he started eating 10 sticks of reptomin a day. Just give it time when he is hungry he will eat. And also my floating dock doesn't have a space between it and the aquarium. Here is a pic of my setup for one baby painted hatchling.