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Fry Care (Live Food)
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The Artemia Revolution
Newly hatched brine shrimps (Artemia Sp.) have been widely used for many years both by commercial and amateur fish breeders. This is due to their high nutritional value and to their availability off the shelf when needed most.
Representing a staggering 35% protein at the time of hatching, the tiny nauplii move readily towards light and their movement attracts fish fry to strike at them and ingest a most natural, vitamin-rich diet which will bring about rapid growth and, most important, survival.
The brine shrimps belong to a group of crustaceans which have been shown by fossil record to have be been an important part of the marine food chain for over 300 million years!
 A phyllopod (many-legged) crustacean the brine shrimp develops directly from the cyst (sometimes referred to as the egg) as a nauplius and then through about fifteen moulting stages called instars to the adult in as little as eight days! Mating then occurs and, depending on the type of brine shrimp and on the environmental conditions the new nauplii will either be born alive or released as cysts, partially developed and protected from an unkind environment until conditions improve and normal development can continue.
Brine shrimps, as their name implies, live in salty waters. These can be either along coastlines where the salt water becomes trapped in pools or in inland salt lakes such as the Great Salt Lake in Utah. In both cases the salt ponds are liable to drying out so that the concentration of salt (salinity) becomes very high.
 Under these conditions the cysts are produced encased in a dark outer shell which provides protection for the embryo inside from the harmful rays of the sun as well as buoyancy so that the cyst floats and can dry out and be blown from pond to pond.
These cysts are produced in vast quantities, under perfect conditions each adult female can produce 300 cysts or nauplii every four days. They can be scooped up from the edge of the pond, washed, dried and stored in sealed cans from which all the air has been replaced by nitrogen. In this way they will remain viable for many years and can be transported around the world for use on fish farms and in the home.
The shell of the cyst (called the chorion) presents one or two problems for fish breeders. It is made of a hard, insoluble substance (mainly chitin, the material of which insect skeletons are made). The nauplius, when it emerges from the cyst causes the outer shell to burst leaving an empty casing.
The empty casing cannot be digested by fish fry and, if swallowed, lodges in the gullet and causes the fry to starve.
In the artificial conditions of a fish farm or home breeding set-up the shells do not get washed or blown away and have to be removed before feeding the nauplii to the fry.
When highly magnified under a powerful microscope the shells can be seen to have a honeycomb structure of passages full of air. It is this structure which gives the cyst its buoyancy. It also gives sanctuary to a host of undesirable bacteria and parasites which may be introduced into the farm or home aquarium posing a threat of diseases to the unfortunate inhabitants.
In the light of these problems it was discovered that the shell could be removed from the cyst by chemical treatment without harming the embryo inside. In fact, after removal of the shell (decapsulation), the hatch rate was even found to be better than before! An added bonus to the decapsulation technique was that it actually killed the harmful bacteria and parasites.
 NT Labs exploited these findings to produce ARTEMIA REVOLUTION decapsulated brine shrimp cysts, preserved in a special fluid which allows them to be stored for many years without losing their viability. Now there was no more need to separate the shells from the nauplii or worry about the possible dangers of introducing disease.
One problem remained, however, having lost their shells the cysts were no longer able to float and in a conventional hatching system most simply sank to the bottom, stuck together in clumps and failed to hatch. In order to overcome this lost buoyancy, New Technology developed a special hatcher which could be installed inside a salt or fresh water aquarium and provide perfect conditions for the nauplii to hatch.
 Apart from breeders who need to use newly hatched nauplii to feed their fry, other fish keepers can benefit from the Artemia Revolution. Brine shrimps can easily be grown to adult size and fed to both marine and freshwater fish - a readily available source of live food. The shrimps are also excellent bioindicators of pollution and are used in laboratories world-wide to assess the levels of harmful chemicals in waterways and marine environments. The simplicity of their culturing, and rapidity of lifecycle, also make them excellent candidates for genetic research. Artemia also show fascinating behaviour throughout their growth process, such as positive phototaxis (movement towards light) and possibly geotaxis (movement towards the bottom of the water).
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