Pebble-Spitting Fish

We caught this Tilapia fish a few months ago with other tilapias and bangus, but my son wanted to save the fish and named him Tilapia and make it his pet. Now we discovered an amazing habit of taking in pebbles inside his mouth and spitting on the aquarium glass just to catch our attention. He is also knocking over rocks and move the small stones into piles then in a few days he will put the pebbles inside his mouth and move it in the opposite side of the aquarium. Enjoy! I'll be posting more videos of Tilapia soon...