Dry Compound Foods.
Commercial dry foods are available in various forms: thin and thick flakes, granules of various sizes and densities, tablets, extrudates, chips, etc. In addition, a number of the companies listed above produce dried planktonic organisms (Daphnia, Cyclops, Artemia, Gammarus, etc., as well as mixtures thereof), dried under special conditions in compliance with strict technologies.
In addition to natural components produced from seafood, fish meat and invertebrates, freshwater and marine planktonic organisms, various types of algae, vegetable, cereal, and herbal components, modern dry foods include essential components such as astaxanthin, carotenoids, vitamins, immunostimulants, and various substances to enhance coloration and strengthen the health of aquarium inhabitants.
Credit must also be given to companies from Asian countries that have developed and manufacture completely different types of dry foods, differing from European and American ones in composition and, so to speak, philosophy. Their formulation is based on the physiological characteristics of specific fish species. It is precisely Asian highly specialized dry foods produced there from local raw materials that are best suited for Asian goldfish and ornamental carps sold worldwide by Asian breeders.
Another type of food that must also be mentioned is professional compound feeds for carp, trout, sturgeon, and other commercial and pond fish species. Some of them are also applicable in aquarium keeping under conditions of large professional facilities. Biomar’s most advanced development is the S-80 series of commercial feeds, which are extremely high-quality, high-protein, and highly nutritious. These are very expensive feeds that undergo special standardization. However, they are far from suitable for all fish species, and they must be fed with some caution due to their excessively high energy value and high protein content.
Overfeeding with such food under conditions of insufficient oxygen can lead to sad consequences. For example, trying to feed goldfish with trout compound feed will lead to severe, even fatal, intestinal inflammations due to the very small amount of ballast substances and fiber in these feeds for this group of fish. Special commercial carp feeds are produced for carp and goldfish, in which fat and protein content is reduced and fiber content is increased.
Commercial compound feeds (Biomar and its analogues) cannot be recommended for amateur aquarium keeping also because they are not sold in pet stores, and buying them by weight at the market should never be done, as improper storage causes them to quickly oxidize and undergo putrefactive processes. Their commercial packaging consists of airtight bags made of a special multi-layer film with selective moisture permeability, in which the foods are kept at a constant low humidity and can be stored for several months. After opening the package, it is advisable to store them at sub-zero temperatures, in the freezer, or at least in the refrigerator. That is why you should not buy such foods at Bird Markets, packaged in plastic bags that do not “breathe”.
Dry single-ingredient (Gammarus, Daphnia, bloodworms, etc.) and other artificial foods (paste, granular, or flake) in the diet of your pets should be a temporary measure. Their types spoil the water to varying degrees and, moreover, do not ensure normal growth, maturation, and appearance in fish.
Flake Foods.
Flakes – Dry food in flake form is ideal for feeding fish living in all water layers of the aquarium, especially those swimming near the water surface. They easily break apart into pieces in water, and even a small fish can easily bite off as much as it can handle. The unique raw material grinding method ensures optimal food assimilation. They have a long shelf life and do not pollute the water.
Recently, flakes have become very popular. They are the easiest to use. The owner does not need to think about whether everyone got enough and whether the food particle size is properly selected. Flakes are readily eaten by most fish species, but in reality, they are not that good. The nutritional value of this food is relatively low – the proportion of binders (gluten, gelatin, agar) is too high, but thin flakes form a very significant contact with water and, even with a slight overdose, significantly worsen its quality.
Flake food is difficult to digest, and it must be chosen after carefully studying its ingredients. Even if everything satisfies you, it does not mean that this food will satisfy your pets. In addition, relatively large fish, eating flakes, leave many small crumbs that then float in the water for a long time, eventually ending up in the filter. There they decompose, creating an additional load on the biofilter. Thus, feeding aquarium fish with flakes is very convenient primarily for the aquarist himself, while the actual needs of the aquarium inhabitants take a back seat here.
However, this ease and simplicity hide a large number of pitfalls. First of all, this applies to manufacturing companies that release low-quality foods into the pet trade that do not meet certain requirements, and sometimes outright “fakes”, often accompanied by solid annotations about the nutritional value and absolute safety of a particular food. Every aquarist must realize for themselves that there is currently no such thing as an absolutely “safe” food of artificial origin. Therefore, any flake food, and along with it any artificial food, should be treated with a certain degree of skepticism, regardless of any advertising assurances from manufacturers and sellers of this product!
The familiar flakes come in all colors and sizes. Usually, they float on the water surface for a long time, making them the preferred food type for surface-feeding fish. Color-enhancing flakes: one of the most common flake foods for fish. They are designed to give yellow, orange, and red fish a richer color due to high beta-carotene and other ingredients. Make sure they contain a high amount of shrimp oil, as it is one of the strongest pigment enhancers.
Growth formula: These flakes contain a large amount of protein for enhanced fish growth. For obvious reasons, these flakes are not intended for feeding already adult fish. Flakes for herbivorous fish. When buying such flakes, check the composition to ensure that Spirulina is present in the prevailing amount. In herbivorous fish foods from very many companies, fish meat prevails rather than Spirulina. The smaller the flake size, the easier they are assimilated by the fish body and the lower the likelihood of gastrointestinal and other physiological diseases. Some types of flake food “swell” for quite a long time and, when eaten in an unswollen state, can cause digestive disorders and gastrointestinal tract lesions.
Flakes do not require preliminary soaking, except in cases where you are going to carry out preventive feeding using liquid or dry medications or feeding with vitamin supplements added to the food. But if you always soak flakes, it won’t get any worse; the only inconvenience is that soaked flakes are not very convenient for dosing. Feeding with pre-soaked flakes is best done using a measuring spoon.
Chips – Something between flakes and granules. Externally, they look like multicolored confetti, significantly denser than flakes, but due to their porous structure, they quickly 
soak in water without losing their shape. Another plus is the almost complete absence of a dust-like fraction, which, as a rule, is not eaten by fish, but only pollutes the aquarium, settling to the bottom or entering the filter.
When entering the water, some chips retain buoyancy for a long time, held by the surface film, while others sink to the bottom quite quickly. For a general aquarium with “mixed” fish, this is a definite plus. After all, with such a dispersal of food, both surface feeders will be fed, and bottom feeders will not go hungry. The component composition of the foods has been significantly expanded due to changes in production technology.
Produced using a low-temperature processing method that preserves all the nutritional properties of the food. Usually, flakes are dried at a temperature of 130°C, whereas in this case, the temperature drying limit is 75°C, which allows preserving most of the vitamins in the final product. For feeding all fish species. They contain significantly more energy than regular flake food. With regular use, it reduces the nitrate content in the water.
Granular and Tablet Foods. Storage of Dry Foods.
Dry Compound Foods. Flakes, Granules, Tablets, Plankton, Jelly. 
