[Killietalk] RE: Killietalk Digest, Vol 5

["Koran, David HQ02" <David_Koran at HQ02.USACE.ARMY.MIL>]

Brine shrimp hatching made easy...

After reading the exchanges for the last few days I just felt the need to
bring the "cheap" back into the process.  

There is every suggestion for hatching shrimp from suspended cones to
special plastic devices.  There are also discussions on using airstones,
heating elements and the need for light.  Well, back to the basics.  As I
have pointed out on several posts, I have been hatching brine shrimp daily
for almost 30 years and it is the primary source of food for my killies.  If
my brine shrimp ain't hatching, the fish aren't doing well.

I have used one gallon pickle jars since 1974.  They work fine, they are
cheap.  Although I set the jar up so it is slightly tipped to one side,
leaving them flat doesn't reduce hatching.  The key to hatching shrimp is
that they need constant movement in the hatching solution.  If you don't
have this, the hatch will be poor.  You accomplish this movement
inexpensively by vigorously bubbling air through the solution/cyst
suspension.  You don't need an airstone to do this and you don't need to
have the air tube go all of the way to the bottom if the "boil" you create
with the air tube is sufficient to keep everything moving.  If it is too
vigorous, once hatching commences you tend to kill the newly hatched shrimp;
however, this needs to be pretty vigorous in order to do in the shrimp.
When you have the confined geometery of the cone, it is critical to make
sure the airtube goes all of the way to the bottom to aggitate the build up
of eggs getting trapped there, in the jar there is almost no place for eggs
to accumulate under the moving current created by the "boil".

I have been using a 1 liter separatory funnel for almost 30 years to
separate nauplii from cyst casings and unhatched cysts but after posting
another suggestion several weeks ago I constructed a makeshift sep funnel
from a two liter plastic soda bottle by cutting off the bottom and replacing
the cap with a push-pull top you find on many of the bottled water
containers.  I simply pour the contents of the hatching (pickle) jar into
the funnel (actually two) that are inverted into two other pickle jars
(improvised ring stands!) and allow the nauplii to separate.  At this stage
I slide open the top/cap of the inverted bottle and release the bottom
contents of the separation into a plastic container stopping at a point
where I think I have the majority of the shrimp captured.  I can slide the
cap closed or simply place my finger over the opening (a little easier to
do).  I usually drain a little more of the suspension into my brine shrimp
net and then dump the remainder into the sink.  A quick water rinse and the
improvised separatory funnel is ready to use again.  If you are trying to
conserve hatching solution (why, I don't know) you can drain solution
through your filter and also return it to the top portion of your suspension
rather than pour it down the drain and try hatching things one more time (I
don't find this particularly fruitful but that is your decision).  The
improvised sep funnel with its two liter capacity is speeding my workup time
but more critical is it is chepaer than fretting over breaking my one liter
glass sep funnel which has a replacement cost of about $100 plus you can
simply disgard the plastic bottle if it gets gummed up.  After several years
you start getting algae growth on the inside of the separatory funnel and it
is difficult to clean it without introducing chemicals or special brushes.

Fortunately I have stockpiled brine shrimp nets after haing difficulty
finding them many years ago but as Erny points out, Bounty paper towels make
good cheap filters.  Simply fold the towel in half and then half it again.
Open at one of the folds to form a cone and seat it inside of a plastic
(cone filter) funnel.  It doesn't fit all around the inside of the funnel
but that fold will form an air channel to allow pressure escape of air as
the solution filters.  Whatever your filtering device, rinse the "cake" of
nauplii into fresh water and feed with either a plastic dropper or glass
pipette.  You can use a rinse bottle (fine tip) to rinse off the shrimp from
the filter material or use a sports bottle with the push-pull tops to
accomplish the same thing.  And never did I mention a siphon in all of this!
Those paper towel filters work pretty good when you are out collecting fish
and you want to place the fish into a container of the water you just
retrieved them in and it is pretty mucky.  Pour the contents through a net
to hold the fish and then the water through a paper towel filter to remove
most of the debris you don't want to take home!  (BTW, Uncle Scotty, my
brine shrimp net sits in my sink inside of an inverted one quart plastic
food container where I cut off the bottom to accept the net and then cut
notches into the top (which is now on the bottom) so the water will drain
out from the container).  The slight taper of the container in the inverted
position give the setup stability and the notches also allow water that may
back up in the sink to prevent the setup from floating and tipping over.)
Cracked one gallon jars that don't hold water make great "ring stands" for
your separatory funnels.  Use a coffe urn brush to clean out your hatching
jars before each use.  Cycle a spare jar and make up the hatch solution
after cleaning but don't start the jar for 24 hours.  Right now, at a room
temperature of about 70-71oF, my premium grade Sanders cysts (Harvest 2002)
are hatching in 40 hours.  

And about those concoctions you use to hatch the shrimp -- kosher salt,
baking soda, hatching catalyst -- I use granular feed salt obtained in 80 lb
bags from a decent farm products store.  If you are near an area where they
raise horses (you should see this outside of any metro area) then there will
be a feed store in the area that sells salt in this form.  You want
crystaline salt without additives.  It should cost about $8-10 for a bag.
That is about a 10 cents a pound.  This is evaporite salt and is probably
produced from "feed" water from where you find shrimp in the first place.

As for the need for light, that is grossly overrated.  You only need enough
light to be able to find your jars to work up.  While shrimp are
photosensitive and swim toward the light, placing a light above your hatch
container and thinking the shrimp will swim toward it when the solution is
bubbling like mad is like thinking you are going to go for a stroll into a
120 mph wind, futile!

Dave Koran
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