So I have been waiting and waiting for my female convict to grow, but it is just not happening. I have had her for around three years now, but she hasn't grown over 3.5 inches. I feed her krill flakes, algae wafers, and the occasional frozen Beefheart. She shares a 55 gallon with a school of 15 black skirt tetras and water parameters are no issue. Any ideas on why she isn't growing or is this size normal for females?