how to hatch, raise and feed brine shrimp eggs
Brine Shrimp Guide
Getting Started, Troubleshooting, Advanced Techniques and Feeding;
The Complete Guide to Hatching and Raising Brine Shrimp
Whether you’re a first-time fish keeper trying to raise baby brine shrimp for your new fry, or a seasoned hobbyist looking to optimise your brine shrimp hatchery setup, this guide covers everything you need to know. Brine shrimp — scientifically known as Artemia salina — are one of the most nutritious and widely used live foods in the aquarium hobby. From understanding artemia cysts and hatch rates, to troubleshooting failures, decapsulating artemia eggs, and growing your colony through to breeding adults, we’ve got you covered.
Interestingly, the same creatures sold as sea monkey animals in novelty kits are the very same Artemia species aquarists rely on daily. Whether you know them as artemia shrimp, sea monkey eggs, or simply shrimp eggs, the biology and technique are identical. Let’s dive in.
brine shrimp for beginners
The “Getting Started” Essentials
ANSWERs to your questions
How Long Does It Take for Brine Shrimp Eggs to Hatch?
This is the single most searched question about artemia brine shrimp, and for good reason — nobody wants to stare at a jar of cloudy water wondering if they’ve done something wrong. Under ideal conditions, brine shrimp artemia eggs typically hatch within 18 to 36 hours. Here’s what shapes that window:
Temperature is the biggest lever
At 28°C (82°F), you’ll often see the first nauplii (newly hatched larvae) emerging around the 18-hour mark. Drop to 20°C and you may be waiting 36–48 hours or more. In Townsville and other tropical Australian cities, ambient summer temperatures can actually push hatching water too warm — above 30°C — which can reduce hatch rates significantly. For consistent results, keep your hatch vessel between 25–28°C.
Egg quality and age matter
Artemia cysts sold by reputable suppliers like BrineShrimp.com.au have a quoted hatch rate — commonly 80–95%. Older stock or improperly stored eggs will hatch more slowly and less completely. If you’re buying brine shrimp artemia eggs in bulk, store the sealed tin in the fridge or freezer to extend viability.
Don’t confuse hatching with “done.”
The first brine shrimp nauplii to hatch carry a yolk sac that is their peak nutrition window. You want to harvest within 6–12 hours of the main hatch event, not 24 hours later. Set a specific alarm for the hours, not just a date.
answers to your questions
What Is the Ideal Temperature for Hatching Brine Shrimp?
Temperature is arguably the single most important variable in your brine shrimp hatchery. Get it right and you’ll have consistent, reliable hatches. Get it wrong and you’ll be troubleshooting failed hatches week after week.
The sweet spot is 25–28°C
This range gives fast hatching (18–24 hours) and excellent nauplii survival. A simple aquarium thermometer and a small submersible heater in a container of water surrounding your hatch vessel is an easy, affordable way to dial this in precisely.
Tropical Queensland warning:
During summer, tap water or water sitting in a warm room can easily exceed 30°C. Above 30°C, hatch rates begin to fall and the nauplii that do hatch are weaker. If your climate runs hot, consider placing your DIY brine shrimp hatchery in an air-conditioned room or using a small fan directed over the vessel to evaporate and cool the surface.
Cold water slows everything.
Below 20°C, artemia eggs will hatch slowly or not at all. A cheap clip-on aquarium heater (25W) is sufficient to maintain temperature in most DIY setups. It’s one of the cheapest upgrades you can make to your hatching routine.
ANSWERs to your questions
Do I Need an Air Pump to Hatch Brine Shrimp?
Many beginners search for low-tech ways how to hatch brine shrimp without an air pump. The short answer: you can, but your results will be noticeably worse. Here’s why aeration matters and what your alternatives actually look like in practice.
Aeration keeps cysts suspended, not settled.
Artemia cysts need to stay in the water column — not sunk to the bottom — for even, rapid hatching. An air stone and small pump circulates the water continuously, preventing dead zones. Without it, eggs settle, oxygen is depleted at the bottom, and many cysts simply won’t hatch.
Manual agitation is a viable but labour-intensive alternative.
If you’re determined to go pump-free, shaking or swirling the hatch vessel every 30–60 minutes can partially compensate. This is impractical overnight and is the main reason pump-free hatching yields are typically 20–40% lower than aerated setups.
A basic air pump is cheap and worth it.
A USB-powered nano air pump costs under $5 and runs off any phone charger. Combined with a piece of airline tubing and a small air stone, this is really the minimum viable DIY brine shrimp hatchery setup. Don’t cut corners here — the pump pays for itself in the first batch.
answers to your questions
Can I Use Regular Table Salt to Hatch Brine Shrimp?
This is one of the most common — and most costly — beginner mistakes. Using the wrong salt is frequently why brine shrimp eggs don’t hatch at all, and it’s entirely avoidable.
Iodized table salt will kill your hatch.
The iodine added to standard table salt as a health supplement is toxic to artemia brine shrimp nauplii. Even small amounts inhibit hatching and kill newly emerged larvae. Never use iodized salt in your hatch water under any circumstances.
Non-iodized salt, sea salt, or aquarium salt all work.
Pure non-iodized cooking salt (check the label), coarse sea salt, or dedicated marine aquarium salt are all suitable. Aim for a salinity of approximately 25–35 ppt (parts per thousand) — roughly 1–1.5 teaspoons per litre of water. A cheap refractometer (~$15) gives you precise readings and removes all guesswork.
Tap water quality also matters.
Heavy chlorine or chloramine in tap water can also impair hatching. Letting tap water sit uncovered for 24 hours dechlorinates chlorine (but not chloramine).
Adding a drop of sodium thiosulfate (available from aquarium stores) neutralises both instantly and is the more reliable approach, especially in areas with chloramine-treated water supplies.
answers to your questions
Does the Light Need to Stay On 24/7 During Hatching?
Light plays a specific and often misunderstood role in triggering the hatch of artemia cysts. You don’t need to leave it on all day and night — but you do need it at the right moment.
Light triggers the final stage of hatching.
Artemia eggs require light to complete emergence from the cyst shell. A strong light source for the first few hours after setting up your hatch is beneficial. After the initial 6–8 hours, continuous lighting offers diminishing returns on hatch rate.
Light is your best harvesting tool.
Once hatched, baby brine shrimp (BBS) are strongly phototactic — they swim toward light. Shining a torch or lamp at one side of the hatch vessel draws the nauplii to one spot, making it easy to collect them with a pipette or small siphon without also pulling in shells or unhatched cysts.
Avoid direct sunlight.
Placing your hatch vessel in direct sunlight may seem like an easy free light source, but it causes temperature spikes and algae growth in the vessel over time. Use an LED lamp or a small desk lamp positioned 15–20 cm from the vessel for controlled, consistent illumination.
Section two
Troubleshooting — “Why Is This Failing?”
Sometimes everything seems right on paper but your live brine shrimp just aren’t appearing. This section covers the four most common failure modes in detail, so you can diagnose and fix problems fast.
your questions answered
Why Are My Brine Shrimp Eggs Not Hatching?
Failed or extremely low hatching of brine shrimp artemia eggs is the most urgent troubleshooting query in the hobby. Nine times out of ten, the cause falls into one of three categories:
Wrong salinity or wrong salt type.
This is the #1 cause of complete hatch failure. If you’ve used iodized table salt, your water is toxic to the nauplii before they even emerge. If your salinity is too high (above 40 ppt) or too low (below 15 ppt), hatch rates drop dramatically. Recheck your salt type and your concentration. When in doubt, start fresh with a clean batch of water and confirmed non-iodized salt.
Temperature out of range.
As discussed, anything below 20°C or above 32°C sharply impairs the hatching of artemia shrimp. Use a thermometer to confirm your actual water temperature — not just room temperature. Hatch vessels warm up and cool down differently than the ambient air, especially plastic bottles or containers.
Eggs are old or degraded.
Artemia cysts have a shelf life. A can of shrimp eggs that’s been open for over a year, or stored in a warm humid environment, will have a degraded hatch rate. Check the manufacturing date on the tin, store in an airtight container in the fridge between uses, and if in doubt, test a small batch from a fresh supply to compare.
your questions answered
How Do I Tell If My Brine Shrimp Eggs Are Dead or Expired?
It can be genuinely hard to tell from appearance alone whether a batch of artemia eggs is still viable. Here’s how to assess quality before committing to a full hatch attempt.
Run a test hatch.
Place a small pinch of eggs (~¼ teaspoon) in a jar of correctly prepared salt water at 28°C with aeration. Check at 24 hours. If you see no movement at all under a magnifying glass or good light, the eggs have almost certainly lost viability. A healthy batch should show nauplii within 18–24 hours under these conditions.
Look for the colour and float test.
Fresh, viable brine shrimp eggs are a medium-brown colour with no grey or black tinge. When placed in water, they should slowly sink or float near the surface before hydrating and hatching. Eggs that immediately clump into a slimy mass may be contaminated or moisture-damaged.
Check your storage conditions.
Opened cans of artemia cysts should be stored in an airtight container (a small jar with a sealed lid works well), kept in the refrigerator, and used within 6–12 months for best results. Freezer storage extends viability to 2+ years. Heat, moisture, and oxygen are the enemies of brine shrimp artemia eggs in storage.
your questions answered
Why Is My Hatching Water Cloudy or Smelling Bad?
Clear, slightly tan-coloured water is normal in a healthy brine shrimp hatchery. Milky white cloudiness or an unpleasant odour is a warning sign that needs attention before it kills your hatch.
Bacterial blooms from overloading.
Adding too many brine shrimp eggs to your hatch vessel creates decaying matter — unhatched shells, dead nauplii — that feeds bacterial growth. A standard 600 ml plastic bottle should receive no more than ½ teaspoon of cysts. Over-seeding is the primary cause of cloudy, smelly hatch water.
Incomplete cleaning between hatches.
Bacteria and biofilm from previous hatches accumulate rapidly in plastic vessels. Between every batch, rinse the vessel with a dilute bleach solution (a few drops in a full bottle of water), then rinse several times with fresh water before refilling. Don’t skip this step even if the vessel looks clean to the naked eye.
Extended hatch time.
The longer you leave artemia brine shrimp nauplii in the hatch vessel after emergence, the more the water quality degrades. As the yolk sac is consumed, waste products build up and oxygen depletes. Harvest within 24 hours of first emergence. The longer they sit, the fouler the water and the weaker the nauplii.
your questions answered
Why Are All My Brine Shrimp Dying Shortly After Hatching?
Seeing nauplii in your hatch vessel only to find them all dead a few hours later is deeply frustrating — but there are consistent, fixable causes. Baby brine shrimp are fragile immediately after emerging.
pH crash.
As artemia brine shrimp hatch and metabolise, they consume oxygen and produce carbon dioxide, which acidifies the water. In poorly buffered water (using plain tap water without any pH adjustment), the pH can drop below 7.0, which is lethal to nauplii.
Adding a small pinch of sodium bicarbonate (baking soda) to your hatch water raises the pH to around 8.0–8.5 and provides the buffering that prevents this crash. More on this in the advanced section.
Oxygen depletion.
BBS need dissolved oxygen to survive. If your air pump or air stone is undersized, or if the hatch vessel is overcrowded, oxygen levels drop and mass die-offs follow. If you’re seeing nauplii gathering at the very surface of the water (where oxygen is highest), that’s a sign of oxygen stress. Increase aeration immediately.
Transferring with too much salt water.
When you move nauplii into a freshwater aquarium, a high volume of salt water follows them. This can stress or kill freshwater fish fry and also degrades water quality.
Using a fine brine shrimp net (100–150 micron mesh) to rinse the nauplii with fresh water before feeding eliminates this problem and also removes much of the metabolic waste in the harvested water.
Section three
Advanced Techniques & Optimisation
Once you’ve mastered the basics of how to hatch brine shrimp eggs, these techniques will dramatically improve your efficiency, hatch rates, and nauplii quality. This is the section experienced hobbyists wish they’d found earlier.
your questions answered
How Do I Separate the Shells from the Baby Brine Shrimp?
Empty cyst shells are indigestible and can block the gut of small fry if fed in quantity. Separating BBS from shells is one of the most important quality steps between hatch and feed.
Use light and gravity.
After hatching, turn off the air pump and shine a light at the bottom of the vessel. Baby brine shrimp swim toward the light; the empty shells float to the top; unhatched cysts sink to the bottom. Wait 5–10 minutes, then use a pipette or small siphon to collect the nauplii from the illuminated lower zone.
This three-layer separation — shells on top, nauplii in the middle-lower zone, unhatched cysts at the bottom — is the most practical method for a DIY brine shrimp hatchery.
Filter through a fine mesh.
After siphoning the nauplii out, pass them through a 100–150 micron brine shrimp net to remove any remaining shell fragments. Rinse under fresh water to remove salt, then transfer directly to the aquarium or a small holding cup.
A purpose-made brine shrimp net is a worthwhile investment once you’re hatching regularly.
Decapsulation eliminates shells entirely.
If shell separation is a persistent challenge, decapsulating your cysts before hatching removes the outer shell entirely. Decapsulated eggs hatch shell-free, meaning there is simply nothing to separate. More detail on this technique follows in the next question.
your questions answered
What Is “Decapsulating” and Do I Need to Do It?
Decapsulation is considered the gold standard technique among serious breeders and aquaculture operations that produce live brine shrimp at scale. Here’s a plain-English explanation of what it is and whether it suits your setup.
Decapsulation.
Decapsulation is the process of chemically dissolving the hard outer shell (chorion) of artemia cysts using a solution of sodium hypochlorite (bleach) and sodium hydroxide (or baking soda).
The exposed embryo hatches faster, shell-free, and with a slightly higher overall hatch percentage. Decapsulated artemia eggs can also be fed directly without hatching — the embryo itself is nutritious even un-hatched, which is a useful option for very small fry.
The process in brief:
Hydrate your cysts in fresh water for 1 hour. Mix a bleach-and-salt solution (roughly 0.5 ml of household bleach per gram of cysts).
Add the hydrated cysts and stir until the colour changes from brown to grey-white to orange (this takes 2–4 minutes). Immediately drain, rinse thoroughly with cold fresh water, then neutralise with sodium thiosulfate solution.
The cysts are now ready to hatch or feed immediately.
Do you need to do it?
Not necessarily. For casual aquarium hobbyists feeding a small number of fish, the standard light-separation method works fine. Decapsulation becomes worthwhile if you’re raising sensitive marine larvae, hatching high volumes of brine shrimp artemia eggs daily, or if shell ingestion has been a documented problem with your fish. It adds 15–20 minutes of preparation time per batch.
your questions answered
How Much Baking Soda Should I Add to the Water?
Adding sodium bicarbonate (baking soda) to your hatch water is a simple technique that dramatically improves hatch rates and nauplii survival — yet most beginners never hear about it.
Use approximately ¼ teaspoon per litre of hatch water.
This raises the pH to roughly 8.0–8.5 and provides a carbonate buffer that resists acidification during the hatch cycle.
Artemia brine shrimp naturally occur in highly alkaline saline lakes (Mono Lake in California, the Great Salt Lake in Utah) with pH levels above 8.0. Replicating that chemistry improves your results noticeably.
Don’t overdo it.
More baking soda is not better. Above ½ teaspoon per litre you start to affect salinity and mineral balance in ways that can reduce hatch rate. Stick to the ¼ teaspoon guideline and measure it properly — “a pinch” is too vague to be consistent.
Test your starting water pH.
If you already use alkaline water (many Australian households are on hard, slightly alkaline mains water), check pH first with a simple dip test strip before adding baking soda. If you’re already at pH 7.8–8.0, you may need less or none. Knowing your baseline means you’re adjusting precisely, not guessing — and consistent chemistry leads to consistent live brine shrimp yields every single hatch.
your questions answered
Can I Hatch Brine Shrimp in a Flat Dish Without Aeration?
The “dish method” is popular in online forums as an aeration-free approach to how to hatch brine shrimp. It works, but it comes with real trade-offs worth understanding.
How the dish method works:
A wide, shallow container (such as a baking dish or petri dish) is filled with a thin layer of salt water and eggs are spread across the surface. The large surface area allows gas exchange without an air pump. Proponents argue the thin water layer keeps artemia eggs from settling deeply, encouraging a decent hatch over 24–36 hours.
The limitations are real:
Dish-hatched nauplii cannot be separated from shells using the light/gravity method, because there isn’t enough water depth to create the three-layer separation. You also get lower overall hatch rates compared to the aerated cone or bottle method. For feeding small numbers of fish occasionally, it’s acceptable.
For anything regular or larger scale, the aerated brine shrimp hatchery method is clearly superior.
The cone method is the hobby gold standard.
Inverted plastic drink bottles or purpose-made acrylic hatching cones allow aeration, light separation, and easy harvest via a valve or pipette at the narrow bottom end. The geometry keeps cysts in suspension, the bottom collects unhatched cysts for easy removal, and the nauplii concentrate at the light source.
This is how every serious DIY brine shrimp hatchery should be set up for consistent, repeatable results.
Section four
Feeding and Nutrition
Knowing how to hatch brine shrimp eggs is only half the picture. How you harvest, rinse, and use your baby brine shrimp — and how you grow them to adulthood — determines whether they’re a premium food source or a wasted effort.
your questions answered
How Long Are Baby Brine Shrimp Nutritious After Hatching?
BBS are at their absolute peak nutritional value in the hours immediately after hatching. Understanding the yolk sac window is the difference between feeding your fish an excellent food source and an empty-calorie one.
The yolk sac window is 6–12 hours after emergence.
Newly hatched baby brine shrimp carry a large, orange yolk sac packed with essential fatty acids (particularly HUFA — highly unsaturated fatty acids) and proteins critical for larval fish development.
This is the entire nutritional case for using live brine shrimp over other foods. After 12–24 hours, this yolk sac is fully consumed and the nauplii are largely carbohydrate-depleted — high in protein but greatly reduced in fats.
Harvest and feed on the same schedule every day.
The simplest way to always feed within the yolk sac window is to hatch on a fixed schedule — set up a batch every evening, and harvest and feed first thing in the morning, 18–20 hours later.
This aligns your harvest with the peak nutrition window without requiring precise timing during the day.
If you can’t feed immediately, refrigerate briefly.
If your hatch is ready but your feeding window is 2–4 hours away, you can slow the artemia nauplii’s metabolism by placing the harvest (in salt water) in the fridge. This buys you a few extra hours without significant nutritional degradation.
Don’t refrigerate for more than 6 hours — the cold eventually kills them.
your questions answered
How Do I Feed Baby Brine Shrimp to My Fish Without Getting Salt in the Tank?
Salt contamination from brine shrimp hatchery water is a genuine concern for freshwater aquariums and marine tanks where salinity must be precisely maintained. Here’s how to feed cleanly.
Always rinse through a brine shrimp net before feeding.
A 100–150 micron mesh net captures the nauplii while the salty hatch water passes straight through. Hold the net under a gentle stream of fresh water for 10–15 seconds to rinse. This removes the salt water and the metabolic waste products that accumulated in the hatch vessel, both of which degrade water quality in your brine shrimp aquarium.
Use a small cup of aquarium water to transfer.
Once rinsed, tip the nauplii from the net into a small cup of water taken directly from the destination tank. This eliminates any temperature or chemistry shock.
Pour the cup into the tank slowly, targeting the area where the fish are feeding. Baby brine shrimp disperse quickly so feed in a calm area with low flow.
Don’t add more than your fish will consume in 5 minutes.
Any uneaten live brine shrimp that die in the tank will decompose and spike ammonia, particularly in smaller or heavily stocked aquariums. Feed conservatively at first, observe how much the fish take in the first few minutes, and adjust the quantity of your next hatch accordingly. It’s better to run two small hatches than one massive oversupply.
your questions answered
How Do I Feed Baby Brine Shrimp So They Grow Into Larger Adult Brine Shrimp?
Growing your artemia shrimp on from nauplii to adults opens up a whole new dimension of the hobby — larger prey items, the ability to enrich and gut-load, and ultimately the potential to establish a self-sustaining colony. Here’s how we recommend you do it the BrineShrimp.com.au way.
Move nauplii into a dedicated grow-out vessel.
Don’t try to grow artemia brine shrimp in your hatch cone — density is too high and waste accumulates too quickly. Transfer hatched nauplii to a larger container (a 2–5 litre tank or container works well) filled with clean salt water at 25–30 ppt and maintained at 25–28°C with gentle aeration. Keep density below 2–3 nauplii per ml for best growth results.
Feed a fine microalgae or yeast suspension twice daily.
Adult artemia brine shrimp are filter feeders that consume microalgae, bacteria, and fine organic particles in nature. In captivity, Nannochloropsis concentrate (available as liquid algae or dried powder from aquaculture suppliers), Spirulina powder, or a suspension of dry baker’s yeast in water all work well. Feed sparingly — the water should become slightly tinted but not opaque. Over-feeding causes bacterial blooms and crashes the colony.
Do partial water changes every 2–3 days.
As artemia brine shrimp grow from nauplii to juvenile to adult (a process taking approximately 2–3 weeks at 28°C), waste and ammonia accumulate rapidly.
Remove and replace 25–30% of the water every 2–3 days with fresh salt water of the same temperature and salinity. Regular maintenance keeps your colony healthy and growing, and is the key step most hobbyists skip that leads to culture crashes.
your questions answered
How Do I Grow My Brine Shrimp to Adults and Trigger Them to Breed and Lay Eggs?
A self-sustaining artemia brine shrimp colony that produces its own sea monkey eggs (cysts) is the holy grail for aquarists who want a continuous, cost-effective live food supply. It’s achievable, but it requires specific environmental triggers.
Raise salinity to trigger cyst production.
Artemia brine shrimp reproduce in two modes: ovoviviparous (live birth of free-swimming nauplii, at normal salinity 25–35 ppt) and oviparous (production of dormant, desiccation-resistant cysts, triggered by environmental stress including high salinity).
To trigger your adults to lay brine shrimp artemia eggs (cysts), gradually raise the salinity of your culture to 50–80 ppt over several days. The females respond to the stress by switching from live birth to cyst production. You’ll begin to see the orange-brown cysts accumulating on the surface and walls of your vessel.
Harvest and dry the cysts for storage.
Collect the sea monkey eggs (artemia cysts) from the water surface using a fine net or pipette, then rinse and dry them on a paper towel in a well-ventilated, shaded spot. Once fully dry, store in an airtight container in the fridge. Properly dried and stored shrimp eggs remain viable for 1–2 years. You’ve now closed the loop — your colony is producing the same artemia cysts you started with.
Maintain a breeding culture separately from your grow-out stock.
The best setup is to run two vessels: a production grow-out at normal salinity (25–30 ppt) where you harvest nauplii and juveniles for feeding, and a breeding culture at elevated salinity (50–80 ppt) where you allow adults to age and produce cysts. This separation prevents juveniles from being crowded out by large adults in the breeding tank, and ensures you always have a fresh nauplii supply from your production culture while the breeding culture does its work. Over time, this makes your brine shrimp hatchery almost entirely self-sufficient.
95% hatch rate guaranteed