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re: retry...decapsulation


For 1362 grams of Great Salt Lake (GSL) strain Artemia eggs:

1)  Hydrate eggs in fresh water for 1 hour with aeration.
2)  Once hydrated, strain eggs from water using a 150 micron mesh.
3)  Prepare chlorine solution:

		- 185 ml sodium hydroxide (NaOH) or caustic soda (liquid)
		- 260 grams sodium chloride (NaCl) or rock salt.
		- 7.415 liters fresh water

4)  Add hydrated eggs to the chlorine solution and mix using aeration.
5)  Add 2.0 liters of sodium hypochloride (liquid bleach - 12% active
6)  Monitor time of reaction and temperature (not to exceed 40 degrees
7)  Maintain vigorous aeration or mixing.  Reaction time ranges from
5-10 minutes.
8)  Color change in eggs is from brown-grey-orange.
9)  Stop reaction when 90% of eggs are orange.
10) Pour eggs and solution into 150 micron mesh and rinse immediately
with fresh water.
11) After 5 minutes (or more) of rinsing, remove excess water.
12) Transfer eggs to the Artemia hatch tank at a stocking density of 2

13) If storing eggs for later hatches, add eggs to 10 liters of water.
14) Add 115 ml of muratic acid or hydrochloric acid (37% AI) for 1
15) Rinse and dewater eggs and add brine water (300 ppt) until covering
16) Store in refrigerator up to 30 days.

12/12/94 9:14 AM

Decapsulation of Artemia Cysts


One pint or 16 fl oz. of fresh water			
2 oz. of liquid chlorine bleach
1 tablespoon of white vinegar
1 teaspoon of brine shrimp cysts

Begin by adding 3 oz. of chilled fresh water and one teaspoon of brine
shrimp cysts to a glass container.  Using an air stone, gently aerate
the cysts for approximately one hour at room temperature.  This will
fully hydrate the eggs in preparation for the decapsulation process. 
After one hour, pour in 2 oz. of liquid bleach.  Increase the aeration
or stir continuously for the next 5-10 minutes (until decapsulation is
complete).  The cysts will change from brown to gray to white, and
finally to orange in color.  When almost all of the cysts are orange,
stop the reaction by pouring the solution into a fine mesh net and rinse
immediately with fresh water.  Continue rinsing until the smell of the
chlorine bleach is gone.  Mix 1 cup of cold water and 1 tablespoon of
white vinegar in a container and soak the net mesh with the cysts for
about one minute.  This will remove or neutralize the residual chlorine
bleach.  Rinse the cysts one more time with fresh water.  Your cysts are
now ready for hatching!

Why Decapsulation?

There are several advantages for decapsulating or removing the thick
outer shell (corion) of the brine shrimp cyst.  

1)  For starters, the strong chlorine or oxidizing solution completely
sanitizes the cysts, reducing introduction of bacteria and diseases to
your aquarium.  

2)  Harvesting brine shrimp nauplii from decapsulated cysts means that
no separation of the shells is necessary.  Just pour everything into a
mesh net, rinse, and feed to your fish!  

3)  Even the unhatched cysts are edible!  An unhatched decapsulated cyst
is left with a thin “hatching membrane” which is easily digested by
young fish and invertebrates.  An unhatched brine shrimp embryo also
contains more energy than a hatched, swimming brine shrimp nauplii.  

4)  The brine shrimp embryo also requires less energy to break through a
hatching membrane than a thick outer shell.  This can increase your
hatch rate another 10% over undecapsulated cysts!