ALGAE IN SHRIMP PL’S RACEWAYS
From: ohenning@lava.net
To: shrimp@yahoogroups.com
Sent: 01 February 2001
QUESTION:
I move PL-4 out of the hatchery to outdoor second
fase LRTs. I fertilize those tanks and inoculate algae from the algae room
(Chaetoceros, Tetraselmis) and from a pond. The survival and growth have
been very good but I would like to know what type of algae (Navicula, etc)
other hatcheries use from PL onwards, in a second phase.
Oscar L. Hennig
Research Associate
Shrimp Program
The Oceanic Institute
P.O. Box 1423
Kailua-Kona, HI 96745, USA
Phone: (808) 329 9293
Fax: (808) 329 7940
E-mail: ohennig@lava.net
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COMMENTS 1:
I prefer green algae like Chlorella sp. for the
outdoor nursery tank. Diatoms and blue green algae are not easy to maintain
(fast bloom, fast crash), pH is also high (9+) when they bloom before they
crash. Chlorella is easy to maintain and makes water pH stable even if they
bloom in the tank.
Khamron W.
BIOTEC, Thailand
bangron@hotmail.com
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COMMENTS 2:
Several of our AquaMat® customers have had good
success in their 2nd stage LRTs (>PL-4) using the benthic diatoms Amphora
and Navicula. They are available as follows:
Amphora coffaeformis CCMP#128
Navicula inserta
CCMP#542
Provasoli-Guillard National Center for the Culture of Marine Phytoplankton
Bigelow Laboratory for Ocean Sciences
West Boothbay Harbor, ME, USA
Tel: (207) 633-9630
Fax: (207) 633-9641
Turns out these genera are well distributed worldwide and a Mexican client
has had equally good success using a locally isolated species of Amphora.
Jeffrey J. Peterson
AquaMats® for Aquaculture Division
Meridian Aquatic Technology, LLC, USA
Tel: 904-491-1905
Fax: 904-491-5015
Email: jpeterson@aquamats.com, pete31405@aol.com
Web: www.aquamats.com
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COMMENTS 3:
I imported these two species - still have them in
test tubes, but failed to get robust cultures. Compared to growing
Chaetoceros sp., Tetraselmis sp., Isochrysis sp. and Skeletonema sp., these
two mentioned algae are difficult to grow. I appreciate advice from anybody
actually using them practically on a commercial scale.
Laurence Evans
E-mail: laurence@amatikulu.co.za
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COMMENTS 4 :
I was interested in finding out more information
about this use of the benthic diatom Amphora coffaeformis in shrimp larval
rearing. I have heard that this Amphora sp. has been associated with a
domoic acid toxin that in effect binds onto the neurons of invertebrates,
essentially popping their brain cells...
I have heard
of this toxin affecting wild stocks of blue mussels and anchovies. Does
anyone have any more information about the specific outbreaks of the toxin,
or if this toxin has been reproduced in culture?
Michael Haring
The Oceanic Institute
Ph# (808) 329-9293
email mharing@lava.net