TUBIVIT Tubifex flake food. TUBIVIT is a high-protein flake food for everyday feeding of fish whose diet is rich in aquatic invertebrates, e.g.: mosquito larvae. It is manufactured from the best quality ingredients, including specially prepared and purified Tubifex. Using TUBIVIT, you can supplement your fish’s diet with popular aquatic invertebrates, avoiding the danger of pathogens present in live and frozen foods.