This is intended as an additional
guide to help with the growing of Artemia. There is an article
on Artemia in the library. You can find it here. http://www.seahorse.org/library/articles/artemiaGuide.shtml
Here are some tips on how to improve the cultivation of
Light is essential for Artemia to hatch. A light sensitive
enzyme in the egg converts a substance called Trehalose into
Glycerol when exposed to light in water. This sugar is hygroscopic
(it attracts water), so the influx of water through the tough
membrane into the egg by osmosis causes it to burst thus releasing
the naupliu. Thus the whole hatching process is dependant
on the presence of light. Normal aquarium fluorescent tubes
tungsten bulbs or even daylight are perfectly adequate for
hatching the shrimps.
Heat is useful for the speeding up of the hatching process.
Heat can be provided nicely by the light bulb you are using
to provide the light from step one. Be careful NOT to let
the Artemia get too hot - they should not exceed 27 degrees.
Feed the hatched shrimps (called nauplii) immediately after
hatching. Providing conditions have been ideal for the shrimps
to hatch (water chemistry, aeration, light etc), the majority
of the nauplii should have hatched at around 18 hours. At
this stage of their life the shrimps are feeding from their
oil reserves, which give them their red-orange colouration.
It is due to these oil reserves that newly hatched Artemia,
are such a valuable food source for fry. The shrimps should
be fed to the fry as soon as possible after hatching to ensure
maximal oil content.
At the stage that the nauplii hatch, they have no mouthparts,
so trying to enrich them is pointless. Around about 24 hours
after hatching the shrimps will have moulted into the second
larval instar, which has a fully formed digestive tract, including
functional mouth and anus, and this critter can feed on bacteria,
algae, detritus or Enrichment Solutions..
To grow the shrimps on to the centimetre long adult stage
is a rather tricky process to do in the home, and will take
a lot of trial and error to find the right procedure. There
are two alternatives available:
Firstly the shrimps can be grown in small vessels such as
a drinks bottle. This method can deal with a high stocking
density of shrimps, but it involves an almost complete saltwater
change every day. One hatch of shrimps can be placed in two
2 litre bottle for example. However as there is a massive
build up of waste products like Ammonia and Nitrite, it is
essential to change the water the shrimps are being reared
in every day. Pour the old water away over a brine shrimp
net to prevent loss of the shrimps and add some new freshly
made salt water. You can use the water from your tank to grow
your Artemia, as this has a bacteria, algae and organic compounds
that the growing Artemia need. Never return the old shrimp
water back to your marine tank as the levels of Ammonia and
Nitrite will be very high.
The other alternative is to establish a filtered system that
requires far less water changing and general maintenance.
The problem with this method is that it is extremely difficult
to establish in the home, and requires a much lower stocking
density than the previous method. The lower stocking density
lowers pollution levels so that a biological filter can process
the waste. In this system one hatch could be placed in a large
bucket with a sponge filter, or an old tank with an under
Both systems require vigorous water movement and aeration.
The best way to do this is to construct an Air-Water-Lift,
like those found on an undergravel filter. This circulates
the water and prevents stagnation, and also aerates the water
adding oxygen and removing carbon dioxide.
Artemia prefer high pH, SG and Carbonate hardness (KH). For
an optimal hatch rate a pH of around 9 a SG of around 1.030
and a KH of over 10 dKH is optimum. They will hatch in water
of lower pH, SG and KH, but the hatch rate is occasionally
impaired. One way to raise the pH and KH the water for Artemia
is to add a teaspoon of bicarbonate of soda to a 2 litre bottle
Once the shrimps have been growing in the rearing vessel
for a number of days, a slime is noticeable on the walls of
the vessel. This slime contains algae and bacteria on which
the shrimps will graze and add extra nutritional value for
the growing Artemia. Don't clean this from your tank. It is
good to have this in an Artemia tank.
When using older Artemia as a food source, you first need
to feed the shrimps. They will pass on any nutrients to the
fry that eat them. There are special enriching fluids that
you can buy to 'gut feed' the Artemia. These are fats in an
emulsifier. The Artemia will pack their stomachs with these
fats, making their nutritional value quite high. This will
usually jam up the internal workings of Artemia, and they
will usually die within 36 hours of enrichment. Typically
you want to enrich Artemia for 6 to 8 hours maximum, then
RINSE WELL and feed.