Building a hatchery on a kitchen counter
Hatching brine shrimp is genuinely simple: salt water, warmth, light, and air will do most of the work. Growing that first batch of nauplii into adults takes a little more attention, but nothing exotic.
A short, forgiving supply list
Cysts
Dried Artemia eggs, from an aquarium store or a hatchery/aquaculture supplier.
Non-iodized salt
Kosher salt, solar salt, or aquarium-grade marine salt — never iodized table salt.
Aeration
A small air pump and air stone to keep cysts suspended and oxygen levels up.
Light & warmth
A lamp and, ideally, a small heater to hold water around 78–80°F (25–27°C).
From dry cyst to swimming nauplii
Mix the hatching water
Dissolve non-iodized salt into dechlorinated water to a salinity of roughly 30–35 parts per thousand — noticeably saltier than seawater. A cheap aquarium hydrometer takes the guesswork out of this.
Add the cysts, light, and air
Sprinkle in the cysts, keep a light on nearby (hatching improves with light exposure), and run steady aeration so the cysts stay suspended rather than settling and going anoxic on the bottom.
Hold the temperature and wait
At around 78–80°F, most cysts hatch within 24 to 36 hours. Cooler water simply slows the process down rather than stopping it.
Harvest the nauplii
Turn off the air briefly and shine a light at one spot — free-swimming nauplii are drawn to it and cluster there, making them easy to siphon out separately from the floating, empty shells.
Taking nauplii to adulthood
Nauplii are usually harvested right away as live fish food, but they can also be grown out into adults with a little more care.
Give them room and surface area
A shallow, wide container — a plastic tub or tray works better than a tall jar — keeps oxygen levels higher and gives a growing population more room to spread out.
Small amounts, often
Once the digestive tract opens (after the first molt or two), feed tiny amounts of powdered spirulina, baker's yeast, or a commercial microalgae paste. Overfeeding is the most common mistake — leftover food fouls the water and crashes oxygen levels faster than it feeds anything.
Keep it clean
Partial water changes and steady aeration matter more as the population grows. Brine shrimp tolerate a fair amount, but ammonia buildup from uneaten food or waste is the main cause of a crashed culture.
Keep them on their own
Brine shrimp cultures don't mix well with fish or other tankmates — the salinity they need would harm most freshwater species, and most predators would simply eat the crop before it matured.
Curious about the pre-packaged version of this exact process? The novelty-pet kits on the Sea-Monkeys page follow essentially the same steps, just with the salt, food, and cysts pre-measured into little foil packets.