03/28/2026
This is a short video of one of my brine shrimp cultures. Yep: You can raise your own brine shrimp! The vid is straight from my phone - not a microscope.
Many people feed baby brine shrimp (BBS) to hatchling axolotls. The eggs (cysts) of the species Artemia franciscana, harvested from the Great Salt Lake in the USA, are relatively inexpensive, easy to obtain, and can be stored under refrigeration almost indefinitely. When submerged in warm saltwater, the cysts hatch into nauplii within about 24 hours. You can feed them to hatchling axolotls (or fish fry - whatever).
Brine shrimp can tolerate any level of salinity between 1% and 5% (10–500 g/L). That means that perfection is unnecessary when hatching and rearing brine shrimp: Just get the salt level about right, and all is well. I use a heaping tablespoon of non-iodized table salt per quart of water, a concentration of about 3%, to hatch cysts.
The hatchling brine shrimp, called naupali, are an excellent food source, high in protein and fats due to the yolk stored in their gut at hatching. A lot of their nutritional value is lost over the next 48 hours as the yolk is consumed. Nutritional value can be restored by “gut-loading” the BBS by feeding them a blend of yeast, spirulina, and/or finely crushed “goldfish flakes”. Just be careful not to overfeed, as excess food quickly rots, fouling the water and poisoning the BBS.
But keep in mind that BBS are really only appropriate for the first few weeks of an axolotl's life. As the axolotl grows, its nutritional requirements increase, and the size of its food sources should also increase.
An easy way to provide a larger, nutritionally complete food source is to simply raise brine shrimp to maturity. Brine shrimp will grow from near-microscopic hatchlings into 10-15mm adults very quickly - in as little as 10 days at 80F. A colony will provide a range of sizes that can feed axolotls throughout their first three months of growth.
I have always raised Moina and Daphnia pulex for my hatchlings, and Daphnia magna for larger larval axolotls. These species can be a challenge to produce in large numbers, though, unless you have a LOT of space and time available for storage and maintenance. I have hundreds of gallons of these cultures in production during the Winter breeding season.
Brine shrimp can be produced in ASTONISHING quantities with little space and effort. The adult shrimp are a perfect intermediate-size food for 2-3 month old axolotls (after which I have transitioned them to pelleted foods).
If you keep a few of the naupauli in 1-5 gallon containers with a bubbler to circulate water and maintain high oxygen level, the brine shrimp will develop into mature adults between 8 and 15 mm long in one to three weeks. I feed them a pinch of crushed goldfish flakes every day or so.
Rate of growth depends primarily on temperature. I raise mine at 80F, which produces mature, breeding adults in under 10 days.
The optimal salinity for adults is around 2%, so I gradually reduce the salinity from the hatching concentration by adding tap water to the culture a bit at a time as the babies grow, reducing the salinity to around 2% for breeding cultures.
They are sexually mature and begin reproducing as soon as they reach adult size.
Mature adults breed quickly. Female brine shrimp produce eggs about every six days. In favourable conditions, the female brine shrimp produce eggs that almost immediately hatch. In more extreme conditions they form cysts with a harder, darker chorion shell that protects the embryo until conditions are better.
Adults continue to reproduce throughout their lives, which typically lasts 3 months or so - though I’ve kept a few individuals for just shy of a year!
You can see mating pairs of adults in the video, with the slightly smaller males clinging to the females. Many of the females have brown cysts attached to the base of their tails, waiting to be dropped to begin the next generation.
In the water around them you see the swirling, cloudy mass of stuff? That’s BABIES! Each little black dot in that cloud is the single eye of a little brine shrimp nauplius. These cultures just keep on producing, converting the food they are given into edible biomass very efficiently.
