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RE: unproductive bs

I struggled with BS culture for a very long time.  I now have a protocol
which works fantastic.  My 12 - 18  year old students can make it work the
first try.
BS are hatched (in normal fashion) in inverted 2 liter bottles and harvested
after 48 hours.  They separated from empty cysts and moved to growout
aquarium.
I know that many advocate conical bottoms for growout aquarium, but we have
found that we do not need them if we hatch the naupli first and transfer
them. For growout aquarium we use 28 5 gallon aquarium, a 30 gallon garbage
can, a 25 gallon "muck bucket". two 20 gallon aquarium, and various plastic
"sweater boxes" or storage boxes.  They all work fine.  We have also
experimented with various substrates, but find that no substrate works
best...except we add a bit of used activated carbon each week (about 1g/l).
First I use synthetic sea salt. Other(homemade) mixes have not worked for me
beyond the first week.  In my case I reuse the water which I remove from the
marine aquarium in my classroom.  The water is about 3.5% salinity..or..with
a specific gravity of about 1.026.   This is heavily aerated for the first
week, moderately aerated the second week, and gently aerated then after.
Twice a day we mix up (scale to your needs) 1 tbs. spirulinia powder
(expensive but worth it) in 1.5 liter of pure water.  This is blended for
4 - 5 minutes.  The suspension of spirulinia is allowed to settle for the
next 5 to 10 minutes. As it settles the liquid suspension forms on the
bottom and a foam layer on top.  The suspension is poured through a brine
shrimp net to remove larger particles and most of the foam.  This liquid is
then added to bs aquarium at a rate of about 10 - 50 cc per 20 liters - but
only in aquarium which have cleared out the previous feeding and resultant
bacterial cloud from the water.  The amount depends upon the feeding rate of
that particular aquarium.  It is surprising that when we measure the
dissolved oxygen tolerance - we have found that shrimp surviving DO
concentrations below 1 mg/l.  Which brings me to color.  If the DO is low
over a sustained period of time - say a 5 to 7 days, you will notice the
shrimp changing from a green to reddish.  This is reportedly caused by
development of an oxygen carrying pigment - hemoglobin or similar pigment.
Synthesis of a substance (any substance) is metabolically costly so
undoubtedly the nutrient value, growth rate, fecundicity, or some other life
parameter is compromised with lower dissolved oxygen rates.
Harvest is done with a standard aquarium net.  The larger netting allows
immature shrimp to remain in culture.  Cultures which are not overharvested
will become self sustaining in 4 to 6 weeks.  Water changes can be minimized
with the addition of 1g/l of used (or new if you have the $) activated
carbon.
This brings me to another point.  Our high school aquatic biology program is
not funded beyond the most basic (paper pens).  We rely upon donations and
recycling everything possible.  If anyone has used activated carbon, light
bulbs, trade magazines, books, retired reef lights, hardware of any kind, or
livestock, and would like to donate it (tax purposes?) please contact me @
mr_page at hotmail_com or rs_page at owt_com.

R. Scott Page
Aquatic Biology Instructor
Hanford High School
http://208.8.74.200

-----Original Message-----
From: Owner-Live-Foods at actwin_com [mailto:Owner-Live-Foods at actwin_com]
Sent: Wednesday, November 18, 1998 12:58 AM
To: Owner-Live-Foods at actwin_com
Subject: Live Foods Digest V2 #257


Date: Tue, 17 Nov 1998 18:29:29 -0700
From: ruddigar at home_com
Subject: unproductive bs

I have am hatching bs in a four gal tank.  When I started it I added
three gals of water, three tblsp aquarium salt and three tsp epsom
salt.  The first week was great!  I had enough to feed my pygmy corys
*and* my apistos.  Now, however, in the second week, I barely get enough
to feed my corys.
	I did a gal water change a few days ago and replace all the water I
siphon out wiht new water (w/ salt).  I have two airstone in the tank,
one at each end and the temp. is about 76F (use a heating pad an low to
heat the tank).

	Any suggestions on how to get my yeild back up?

Thanks,

Jason Miller
Sherwood Park, Alberta