Classification and Taxonomy
Kingdom: Animalia Phylum: Arthropoda Subphylum: Crustacea Class: Branchiopoda Order: Anostraca Family: Artemiidae Genus: Artemia Species: Artemia salina
Scientific name: Artemia salina (Linnaeus, 1758)
Brine shrimp inhabit salt lakes and lagoons across nearly every corner of the planet. Due to their unique biological characteristics, they have become a model organism for scientific research. In commercial fish farming and aquarium keeping, brine shrimp serve as an indispensable food source for raising fish fry.
Distribution and Habitat
Brine shrimp is a collective name for seven identified bisexual species. The original Artemia salina, described by Carl Linnaeus around 1758, inhabited Lake Lymington in Britain. Today, that lake no longer exists, and the species that lived there is officially considered extinct. However, among aquarists, the name has stuck as a common designation for all European Artemia species.
Seven main species exist today:
- Artemia tunisiana (North Africa, Europe)
- Artemia species (parts of Europe, America, Asia)
- Artemia franciscana (parts of Europe, America)
- Artemia parthenogenetica (Australia, Africa, Europe, Asia)
- Artemia sinica (China, Central Asia)
- Artemia persimilis (Argentina)
- Artemia urmiana (Iran)
Brine shrimp inhabit chloride, sulfate, and carbonate waters, with salinity in some reaching 300 grams of salts per liter. At such salinity levels, no other organisms can survive except brine shrimp and certain species of unicellular algae. This ecological barrier protects the shrimp from potential natural predators that cannot tolerate these extreme conditions.
Description and Biology
Depending on species and habitat, brine shrimp display certain variations. Adult body length ranges from 10 to 20 millimeters. Adult shrimp possess three eyes and 11 pairs of legs. One simple eye appears during the nauplius stage, while two more complex eyes develop in adults.
Brine shrimp are thermophilic summer organisms, with optimal temperatures for active life phases between 25–28°C. Water salinity can influence morphology and reproductive method. As early as 1875 and 1877, Odessa biologist V. Schmankewitsch demonstrated that salinity determines morphological features in A. salina—including furca length, setae arrangement, and other characteristics.
Some species are capable of parthenogenetic reproduction. Environmental conditions strongly influence reproductive methods. Under optimal conditions, females can carry eggs inside their brood sacs until they develop into nauplii. A female’s egg sac may contain up to 200 eggs.
When conditions deteriorate sharply—reduced food availability, sudden temperature drops—females release cysts with remarkable survival capabilities. During drilling near the Great Salt Lake in Utah, a soil sample between two salt layers contained A. salina cysts. After incubation, nauplii hatched from these eggs. Radiocarbon analysis dated the layer at approximately ten thousand years old.
Newly hatched nauplii average 0.45 mm in length and weigh 0.01 mg. They do not feed until their first molt, which occurs within 10–12 hours. After transitioning to the second larval stage, they begin filtering water and consuming bacteria, unicellular algae, and detritus. Under optimal conditions, they can reach adulthood in eight days after completing up to fifteen molts. Brine shrimp live approximately six months.
Nutritional Value
The chemical composition of brine shrimp is characterized by high protein content, fats, essential amino acids and fatty acids, vitamins, hormones, and other biologically active compounds. Artemia protein contains 18 amino acids, eight of which are essential: threonine, valine, methionine, isoleucine, leucine, phenylalanine, lysine, and histidine.
In my experience, this high nutritional value makes brine shrimp one of the best starter foods for fish fry. Nauplii contain approximately 50% protein and 7% fat in dry matter, ensuring rapid growth of young fish.
Brine Shrimp as Aquarium Fish Food
Brine shrimp serve not only as food for aquarium fish but also for commercial species on fish farms. When raising sturgeon fry, this crustacean is indispensable, as sturgeon refuse non-living food regardless of nutritional value. Technologies have been developed for maintaining and breeding these crustaceans on industrial scales.
For aquarium hobbyists, purchasing cysts and hatching nauplii using Weis apparatuses is more practical. For some fish, even this step can be skipped. Pet stores often stock decapsulated A. salina eggs, which many fish fry consume eagerly.
Fry of egg-laying species are typically transitioned to A. salina nauplii once they outgrow infusoria. Large fry of nearly all livebearers and some egg-layers can consume eggs or nauplii from their first day. For example, convict cichlid and paradise fish fry readily accept brine shrimp nauplii in their early days.
Feeding Decapsulated Cysts
Cysts for feeding fry must be decapsulated. Feeding decapsulated cysts is not only simpler but also safer. Before feeding, soak decapsulated eggs in water for twenty minutes, then rinse them under running water in a fine mesh net to remove decay products that may have formed during storage.
This eliminates the need for incubation and building an incubator. The risk of introducing infections to the grow-out tank is virtually eliminated. The possibility of nauplii attacking fry is completely excluded—something that can occasionally occur in marine aquariums because A. salina nauplii grow much faster than the fish fry being raised.
Feeding eggs has one drawback: eggs sink to the bottom instead of swimming in the water column. Not all fish fry can pick them up from the substrate. The only solution is constructing a Weis apparatus and hatching nauplii immediately before feeding.
Weis Apparatus for Hatching Brine Shrimp
The simplest Weis apparatus consists of an inverted plastic bottle. Cut off the bottle’s bottom. Attach an air diffuser to the cap or neck by any convenient method. You will need two such bottles.
Fill each bottle with one liter of regular table salt or, preferably, marine salt solution. Avoid iodized salt or salt with additives. Prepare the solution using three level tablespoons per two liters of water (approximately 25-30 g per liter).
Incubation Conditions
Optimal incubation conditions for cysts include: water temperature 26-28°C, pH 8-9, salinity at least 18 ppt, density 2-2.5 g eggs per liter of solution, and lighting at 2000 lux. In my experience, maintaining these parameters ensures maximum nauplii yield.
Add one level teaspoon of A. salina cysts per liter of water to the bottle. While this crustacean is highly prolific, a 40 percent hatch rate is considered excellent in home breeding, so use cysts in slight excess.
Culture Rotation
After 24 hours, charge the second bottle with eggs in the same manner. After another 24 hours, nauplii will appear in the first bottle, ready to feed fry, and the empty container can be recharged with fresh eggs.
Adjust airflow to the diffusers so eggs remain suspended rather than settling to the bottom. Maintain temperature at 28–30°C.
Approximately half an hour before feeding fish, stop the air supply. Empty shells will float to the surface, while unhatched cysts sink to the bottom. Nauplii swimming in the water column can be siphoned through a fine mesh net using a tube. The filtered salt solution can be returned to the incubation container.
Place nauplii in a jar of fresh water for additional rinsing to remove salt, then feed them to fry. Note that even the hardiest A. salina individuals survive no longer than six hours in freshwater.
When feeding marine fish fry, provide only the amount of brine shrimp nauplii that will be immediately consumed. Otherwise, due to the crustacean’s significantly faster growth rate, predator and prey may swap roles within days.
Brine Shrimp in Aquarium Fish Diet
Proper aquarium fish feeding requires variety. Alongside brine shrimp, I recommend using other live food types. Bloodworm and tubifex complement the diet of growing fry and adult fish well. However, for starter feeding during early developmental stages, brine shrimp remains irreplaceable. A comprehensive approach to goldfish food or catfish food should include live options when appropriate.
Interesting Facts About Brine Shrimp
Never sleeps. A. salina cannot sleep. To feed and breathe, it must remain constantly active.
Ancient species. Brine shrimp have inhabited Earth for approximately 100 million years, making them contemporaries of dinosaurs. Only the tadpole shrimp (Triops cancriformis), which appeared over 220 million years ago, is more ancient.
Space traveler. Brine shrimp traveled to space orbit, where a joint Soviet-French crew studied the effects of cosmic radiation on living organisms using this species.
Three eyes. Brine shrimp possess three eyes. One simple eye appears during the nauplius stage, while two more complex eyes develop in adults.
Swims upside down. Unlike most aquatic animals, brine shrimp swim upside down.
This remarkable creature cannot beautify an aquarium, and long-term maintenance presents certain challenges. However, if you plan to breed aquarium fish, understanding this valuable food source is essential for success.
Article updated: 2026-10-30
