I feed my betta bloodworms and pellets but he also likes to eat the flake food that I put in for the other fish. He usually manages to eat one or two flakes but after that... it looks like pieces of the flakes are coming out from his gills! is this normal??
That is normal. Have you ever seen an Oscar or big clown knife or arowanna whack a big goldfish? Scales galore are "blown" out through the gills. It's not a problem. He is crushing them with his pharyngeal "teeth".