Tetras are popular aquarium fish. While they are not particular about their foods, to see your tetras at their absolute best you should vary their diet. There are a wide variety of foods that are great for tetras and you should mix it up as much as possible.
Prepared foods include pellets, wafers and flakes. Fish flakes are often the bulk of an aquarium fish's diet. However, there are varying types of flakes available. You should look for flakes that are mostly meaty with some vegetable matter, as this mimics the diet of tetras in the wild. Also, avoid flakes that contain fillers like wheat. It is also advisable to feed tetras vegetable flakes, preferably containing Spirulina algae, a few times a week.
Freeze-dried foods are typically made from a single organism. They can include food items like bloodworms or mosquito larvae. Feed them the same way as flake food: You should only feed as much as your tetras can eat in three to five minutes. Additionally, freeze-dried foods can loose their quality, so its best to store them in cool, dry conditions and throw out old freeze-dried food.
Get frozen foods at either your grocery store or a pet shop depending on what you want to feed your tetras. Keep in mind that in the wild, tetras mostly need insects (and their larvae) and tiny crustaceans. You should not feed fish frozen food directly; you can keep a small amount thawed in the refrigerator. Frozen foods sometimes contain vitamins that are lost in freeze-drying.
Tetras are adapted to eating live foods, as this is what they eat in the wild. Some live foods appropriate for tetras include brine shrimp, fruit flies and micro-worms. Collect these from nature, or grow them at home if you don't care to purchase them from a pet shop that carries them. Always take care when collecting live food. If there are fish in the same body of water, there can be parasites.