Summary: This article offers an in-depth look at proper betta nutrition, a much ignored but very important component of good husbandry.

Introduction
There is much talk within the fishkeeping community regarding issues like tank size, stocking, water quality, and species compatibility. One of the most important aspects of fish husbandry, however, has been largely overlooked: nutrition.
Captive fish - regardless of if they are wild caught or fully domesticated - seldom have the opportunity to eat the foods they would be exposed to in their native or ancestral habitats, and rely primarily on a variety of processed foods to survive. As with all animals, these balanced processed diets have their positive and negative attributes that vary based on brand, ingredients, and feeding schedule.
In this guide to betta nutrition, a few common types of betta foods will be explored, pointing out the strong and weak points of each. Good feeding practices will also be addressed, with the goal of helping betta owners choose the best way to maximize nutrition for their pet. This topic can also be used as a place for members to exchange experiences regarding different betta foods.
Betta Nutrition
Bettas are classified as carnivores (or insectivores), and in the wild consume a diet of primarily zooplankton, mosquito larvae, and other insects. They may also prey on the fry of their own or other species of fish. Because of this, a betta's diet should be high in protein and animal products, and low in fiber and vegetable products. Pelleted and flake diets are often composed of ingredients that do not mimic the natural diet, but it is arguably more important to be certain that there is a good balance of vital nutrients and a safe, wholesome source of protein and fat. Live, frozen, or freeze-dried insects, on the other hand, more closely mimic the natural diet, but may not be nutritionally complete unless fed in great variety. To better understand the differences in foods, as well as their pros and cons, please read the section below.
Which Food is Best?
A question often posed to pet nutritionists is "which food is the best?" Though it seems simple, this is actually quite a loaded question, since nutrition is individual and based on circumstance! Regardless of the species, a bare minimum of health, body condition, activity levels, and owner budget must be considered. Additionally, with cold blooded animals like fish, temperature strongly influences metabolism, and thus feeding schedule. Finally, proper nutrition for breeding, growth, critical care, and recovery must also be considered. So, the answer to the question of "which food is best?" is, "it depends..." As a starting point, here are some descriptions of foods for average, healthy, adult bettas.
Flakes
Traditionally, many species of fish have been fed flake diets. Fish flakes are convenient for community aquariums with a variety of species, as they are easy to chew, can be broken into sizes suitable for any species, and are very inexpensive to buy. Not surprisingly, there are many brands of flakes for bettas on the market. There are positives and negatives to these products; on one hand, they are wonderful for small bettas or bettas who have trouble chewing pellets, and have a long shelf life and low cost. However, they also have several serious negatives; flakes have more air than substance, and are thus not as nutritionally complete as pelleted foods. They absorb moisture readily and can thus cause constipation and other digestive difficulties. And compared to most other foods, they have a low palatability.
There are easy ways to cope with the down sides of flakes if they are to be fed as the primary dietary simple. First, all flakes should be pre-soaked. Pre-soaking will allow moisture to enter the flake, reducing the trapped air and the swelling of the flake in the betta's stomach (which could contribute to swim bladder disease). When flakes absorb moisture in the water rather than in the gut, they are less likely to cause constipation. Soaking will also increase the palatability as it will improve the texture and release more of the scent and flavor. Finally, treats of richer foods can help combat the slight nutritional inferiority of flakes.
Pellets
Pellets are increasingly the staple diet of choice among fishkeepers. Pelleted foods tend to be more nutritionally complete than flakes, more gentle on the digestive tract, and are often more palatable to fish. There are a variety of brands of pellets available to betta keepers, from very inexpensive generic brands, to higher quality (and price!) brands such as Hikari and Atison's. These foods do not swell as badly as flakes in the digestive tract, and are readily accepted by most fish as they have become the dietary staple of many fish stores.
This is not to say they lack any negative attributes. Because of the wide range of sizes observed in adult and sub-adult bettas, not all pellets are suitable for all individuals; female bettas, younger fish, and small specimens in general risk starvation, jaw injury, or choking if fed an oversized pellet. Selecting small pellets, and pre-soaking to prevent injury, can greatly reduce this problem If all else fails, most pellets can be easily crushed for smaller fish.
There is also an issue among some fishkeepers regarding the use of preservatives in many brands of pellets. Because pellets can have a higher fat and protein content than freeze-dried flake foods, many manufacturers use preservatives to prevent spoiling. While there is no conclusive scientific evidence suggesting that these substances are harmful or benign, personal experience on both ends of the opinion spectrum leaves plenty of room for personal choice when selecting a pellet brand.
Freeze-Dried Foods
Many invertebrates can be found in freeze-dried forms; blood worms, daphnia, and tubifex worms are among some popular freeze-dried foods used by hobbyists. Like flakes, freeze-dried foods have a long shelf life, are inexpensive, and convenient for the owner. What's more, some chain stores feed freeze-dried foods exclusively to bettas due to their cost effectiveness, so new bettas are normally pleased to eat what they are familiar with.
Unfortunately, freeze-dried foods have many negative traits. They are notorious for creating constipation and swim bladder problems as they absorb moisture quickly in the gut. Some nutritional value is lost during the freeze-drying process, and in the case of tubifex worms, it is possible for cheaper brands to harbor deadly bacteria. Many hobbyists will not feed freeze-dried foods for these reasons, though with adequate pre-soaking, freeze-dried blood worms and daphnia are an enjoyable treat for your betta.
Frozen Foods
Many fish stores have frozen foods available for a reasonable price to the public. They are typically insect-based, which is perfect for bettas, which are insectivorous by nature. Blood worms, brine shrimp, midas shrimp, and other foods are available from a variety of manufacturers, as are mixed-ingredient carnivore diets. These foods are beneficial because they mimic the natural diet more accurately, are extremely rich, highly palatable, and may be fairly inexpensive based on the number of fish you own.
However, one must keep in mind that frozen foods are not nutritionally balanced, and unless fed in great variety may lead to deficiencies and excesses that can be harmful to your betta's health. Furthermore, the richness of these foods promotes obesity, particularly in fish kept in colder aquariums with less swimming space. Finally, frozen foods can be a source of deadly bacteria if stored incorrectly, so always look for signs of re-freezing, and dispose of any excess thawed food after each feeding.
Live Foods
Most betta fry start out on a diet of live foods, such as baby brine shrimp or vinegar eels. Well, adult bettas can certainly have live foods as well! Blood worms, blackworms, brine shrimp, wingless fruit flies, and other readily available invertebrates can be cultured with relative ease or purchased in some pet stores as a supplementary portion of your betta's diet. These foods have the benefit of also serving as behavioral enrichment, as they encourage the betta's natural predatory behavior. They are also highly nutritious as they have not lost any of their value from protein-degrading processes like freezing, drying, or sterilization.
Unfortunately, live foods have a dark side: it is very easy to make bettas ill with contaminated cultures. Blackworms in particular are notorious for causing deadly internal infections, and should only be purchased from a highly reputable source or cultured at home. What's more, live foods can be pricey, either due to the costs of buying and culturing, or the price in pet stores. Because of this, many betta owners choose sterilized frozen foods instead.
Vegetables and "Human Food"
One of the more controversial aspects of betta nutrition regards feeding 'human' foods to bettas. Some fishkeepers promote the use of finely chopped organ and muscle meat from terrestrial mammals and birds as an inexpensive alternative to frozen and live foods due to their high fat and protein content. The presence of bi-products from such animals in some commercially available foods has helped back the stance that this is an acceptable feeding practice - as it may be.
However, one must consider the fact that bettas were never intended to consume cattle, turkeys, chicken eggs, or anything larger than invertebrates. Because of this, it is possible and likely that such foods may be difficult to digest, and more worryingly, may contain bacteria bettas are simply unable to handle. I would also caution fish owners against the feeding of any dairy products to any species of fish; dairy products were intended for infant mammals only, and are known to cause severe digestive problems in virtually any species - even other mammals! As thus, it would be wisest to avoid feeding "human" foods, or only buy them if they are included in a frozen or processed diet that has been specifically designed with carnivorous fish in mind.
Also included in this category is vegetables, such as peas, cucumber, and other popular foods given to aquatic omnivores and herbivores. While bettas have no dietary need for these foods, they may have some healthy benefits if fed occasionally and in moderation; cucumber and de-shelled, cooked peas are a popular remedy and preventative for constipation, for example. They do not need to be a part of a betta's regular diet, but when fed sparingly, appear to create no adverse side effects.
A Brief Note on Variety
If you read the above, snorted, and thought "well that doesn't help me; I still don't know what to feed!" since every food type's positives and negatives were explored, please consider the following. Most animal nutritionists agree that the best way to ensure complete nutrition for your pet is through variety. Because each food as its fortes and failings, it is best to feed multiple foods; this will magnify the benefits and reduce the negatives. What's more, feeding a great variety of foods is more enriching for your betta, providing a valuable source of stimulation that is lost when we stick to just one type or brand of food. That's right - I said brand. Even if all you can afford to feed is flakes or pellets, feeding multiple brands will offer much-needed variety; I myself feed five brands of pellets in addition to frozen and live foods!
Feeding Schedule
Once you've decided which food (or hopefully foods) you'll be offering your betta, there is one piece of the puzzle remaining: how much and how often to feed. Unlike dogs and cats, which thermoregulate internally and can thus have their daily energy requirements computed through a simple equation with relative accuracy, bettas are ectotherms - their body temperature and thus metabolism are dictated largely by the temperature of their external environment. Because of this, feeding is affected not only by age, activity level, food nutrient content, health, and reproductive status, but also by the temperature of the environment.
It is also noteworthy that nutritional needs are always greater when dealing with an animal that is growing, reproducing, sick, injured, or recovering from illness and trauma. Across the species board, a greater need for fat and protien from easily digestable sources is observed in these special conditions, and bettas are no different. Keep this in mind when feeding under special conditions, and adjust the diet and feeding schedule accordingly.
So how do you figure out your betta's daily energy requirements? Trial and error. You can safely assume that your betta should be fed something every day, but figuring out what he or she needs to maintain a good body condition is an art of "guestimation" and adjustment. You can safely assume, for example, that an elderly male halfmoon in a one gallon aquarium at 74 degrees eating only frozen blood worms needs to be fed very little. A growing, egg-laden female plakat in a 20 gallon sorority at 82 degrees eating just pellets, on the other hand, would need quite a bit of food to stay at an acceptable weight.
It is also suggested that bettas be fasted at least one day weekly. Because bettas tend to have a dry food as their staple, and a very high-protein diet, they are prone to constipation. While the feeding of a mashed frozen pea is good for clearing up constipation, prevention is always the best medicine; fasting once or twice per week typically offsets digestive problems in average bettas.
Conclusion
Betta nutrition is an inexact science influenced by a variety of factors. There is no easy answer to the type, quantity, and frequency of feedings. Hopefully after reading this guide, however, you have a better understanding of the food options available to you, and can also better grasp what factors influence a betta's daily caloric needs. Remember, when fed a variety of healthy foods relative to temperature, activity levels, and physical condition, most bettas will remain healthy... giving you plenty of time to focus on water parameters and other fishkeeping worries!

Text and Image (c) Lauren Weeks