Artemia eggs are available from aquarium shops. They are expensive but you can set up a self-perpetuating colony where Artemia breed more Artemia for you. Here’s a simple way of culturing Artemia:
Fill a 2 liter soda pop bottle with salt water to within about an inch of the neck. Add about 1/2 teaspoon of eggs. Insert airstone, turn on valve until you get strong aeration. Angle a light so it shines directly on the bottle and keep it on for 24 hours a day. Most eggs hatch within 18-24 hours. Separate nauplii from eggshells. This is relatively easy because nauplii are attracted by light. Put the mixture in a clear bottle and turn it upside down. The eggshells will float up to the surface. If you then black-out the uppermost part of the bottle, and shine a light at the lower part, nauplii will swim down. Opening the bottle gently should allow you to collect the nauplii. Feed new nauplii directly to young seahorses once the shells are removed. Put extra nauplii into a small aquarium or tub with gentle aeration and rear Artemia by adding a little Artemia food when the water is clear. DO NOT FEED if the water is at all cloudy. Mix a small amount of yeast or commercial Artemia food with water and stir into a smooth paste. It may be necessary to let this sit for a half hour or so. Then add the paste to the Artemia tank until the water is slightly cloudy again. Ideally, Artemia should be fed very little — but often. Ensure that the Artemia tank is aerated constantly. Partial water changes should be carried out weekly.
Artemia take about fourteen days to reach maturity, after which they produce their own eggs. It’s better to have several containers going simultaneously and to take a little from each. Artemia can be reared more simply in the summer by starting an algae culture in a tank outside with plenty of sunlight and adding Artemia adults and nauplii to the mature algae culture and they will culture themselves – however, addition of yeast from time to time seems to help.
We know that the “pregnant” seahorse is really a male because male seahorses, like all other male animals, produce sperm whereas female seahorses produce eggs.
The seahorse courtship is lengthy (requiring 3 mornings), active and colorful. Courtship is similar across species. Shortly after dawn, the male and female come together, the male inflates his pouch with water, and both sexes signal their interest in courtship by brightening significantly. Both seahorses grasp the same holdfast with their tails and begin to circle like merry-go-round horses. At frequent intervals, they release the holdfast and make their way, in tight parallel formation, across the bottom to another holdfast.
The male bends vigorously, jackknifing his tail to meet his trunk, thus compressing the pouch. This motion pumps water in and out of the pouch and closely resembles the motion to release the young at birth.
On the third morning of courtship, the female’s trunk becomes rounded, as she ripens the eggs in her ovary, and her ovipositor begins to protrude. When she is ready to transfer eggs, she releases the holdfast and stretches upward – “points” – as if to rise to the surface, keeping her tail tip on the ground. Eventually the male responds to the female’s pointing, and together they rise through the water. As they ascend, the seahorses face one another with their tails bent back, and the female inserts her ovipositor into the open pouch of the male and releases her eggs in a long sticky string. To transfer the whole clutch takes only about six seconds and then the pouch opening is sealed shut. The pair breaks apart and the male gently sways to settle the eggs in the pouch while both settle down on the bottom with their tails wrapped around holdfasts.