Aquaponics Digest - Wed 12/10/97
Message 1: Digest
from S & S Aqua Farm
Message 2: Re: Re: worms as fish feed
from YankeePerm
Message 3: Re: Australian Possum - Protein Base?
from YankeePerm
Message 4: Re: worms as fish feed
from GCR
Message 5: RE: worms as fish feed
from Mark Andrus
Message 6: Interesting Introduction & Questions
from S & S Aqua Farm
Message 7: Re: Taste of my produce
from S & S Aqua Farm
Message 8: Open list discussions (was worms as fish feed)
from S & S Aqua Farm
Message 9: Re:Tilapia Water Temperature & Nutrient Level
from S & S Aqua Farm
Message 10: Extruders
from S & S Aqua Farm
Message 11:
from Mark McCormick
Message 12: economics/sustainability of production
from Jack Rowe
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Subject: Digest
From: S & S Aqua Farm
Date: Wed, 10 Dec 1997 06:17:05 -0600
At 05:52 PM 12/9/97 EST, you wrote:
> set-digest
++++++++++++++++++++++++++++++++++++++
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S&S Aqua Farm, 8386 County Road 8820, West Plains, MO 65775 417-256-5124
Web page http://www.townsqr.com/snsaqua/
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Subject: Re: Re: worms as fish feed
From: YankeePerm
Date: Wed, 10 Dec 1997 08:56:35 EST
In a message dated 12/9/97 7:41:25 PM, gwatkins@yournet.com wrote:
>Hi Paula,
> My experience with dried worm products is limited to the occasional use
>of freeze-dried tubifex and bloodworms. I found that the fish relished
>them but that feeding had to be limited or digestive problems would
>appear. From what I understand, freeze-drying destroys most pathogens. I
>know that live tubifex, which I've also used, are nasty creatures,
>typically found in sewage effluent, and must be carefully purged before
>feeding and even then I think it's a risky food source. Earthworms, on
>the other hand, I've never considered to be a source of pathogens, but I
>could be wrong.
> My original question which started this thread had to do with raising
>worms, specifically red wigglers, in a greenhouse vermicomposting system
>fed on kitchen wastes and crop residue, or maybe in the beds, as a food
>source for my fish. I would only be feeding them live and was asking
>about their nutritional value. So far I've not gotten an answer but I'm
>still searching. BTW, I followed up on the Perionyx excavatus question
>and determined that they are not a suitable species for a greenhouse
>environment (they're notorious escapees) and that red wigglers are the
>most suitable.
> Regards, Gordon
Any live feed will be superior to process feed for the same reasons that you
get more from fresh tomatoes than from tomato past. In particular, the
enzymes in live food are often beneficial way out of proportion to their
quantity. I've gone the other route--feeding minnows to livestock,notably
pigs, chickens and ducks--with excellent results. The minows always are a
tiny part of the food supply but are a component in a system that produces
very healty animals.
Chinese aquaculturists, whose methods I find rather disparaged on this list in
the brief time I've been lurking, feed maggots. A few dead cats suspended
over water in a net bag result in a steady rain of maggots which a rain,
really bump productivity. If fish are being raised intensively, like any
livestock, they are far more vunerable to otherwise minor changes in diet.
Extensive systems result in a hardier and, in my personal view, superior
animal.
For Mother Earth, Dan Hemenway, Yankee Permaculture Publications (since 1982),
Elfin Permaculture workshops, lectures, Permaculture Design Courses,
consulting and permaculture designs (since 1981), and now correspondence
courses via email. One is now underway. Next Live program: Paraguay,
8/10-22/98. Internships available. Copyright, 1997, Dan & Cynthia Hemenway,
P.O. Box 52, Sparr FL 32192 USA YankeePerm
We don't have time to rush.
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Subject: Re: Australian Possum - Protein Base?
From: YankeePerm
Date: Wed, 10 Dec 1997 09:21:31 EST
In a message dated 12/10/97 6:33:50 AM, you wrote:
>>They are, of course, good to eat. In fact, other New Zealanders have been
>>marketing them to China as "Kiwi Bear." Living on the growing shoots of
trees
>>as they do, you can't imagine a cleaner, more wholesome food. If you have
>>more than you can eat, or more likely want to eat, think about pigs. You
>>would probably have trouble importing pirahna to NZ.
>>
>>For Mother Earth, Dan Hemenway, Yankee Permaculture Publications (since
1982),
>
>The original thread, I believe, was under the subject of extruders for fish
>feed. Perhaps Dr. Doelle or someone else would comment on the process
>required for using this type "protein" as a base for fish feed safely.
I think it is perfectly reasonable to point out that the possums are already
food and do not need to be converted to food. Why not take some of New
Zealands 70 million sheep or 30 million cattle and run them through an
extruder for fish? The answer is obvious. It is the same reason why you do
not fertilize your tomato patch with prime ribs, though they would indeed
break down into good plant food. Aquaculture has the potential to provide
quality food to a world where the undernourished outnumber the well nourished
by about two orders of magnitude. Given the pollution where wild fish stocks
are still available to be harvested, it can also provide a cleaner alternative
for those of us who can afford to be choosey. However it makes no sense to
convert perfectly good meat into perfectly good fish.
For Mother Earth, Dan Hemenway, Yankee Permaculture Publications (since 1982),
Elfin Permaculture workshops, lectures, Permaculture Design Courses,
consulting and permaculture designs (since 1981), and now correspondence
courses via email. One is now underway. Next Live program: Paraguay,
8/10-22/98. Internships available. Copyright, 1997, Dan & Cynthia Hemenway,
P.O. Box 52, Sparr FL 32192 USA YankeePerm
We don't have time to rush.
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Subject: Re: worms as fish feed
From: GCR
Date: Wed, 10 Dec 1997 09:21:02 +0000
Earthworms, on
>the other hand, I've never considered to be a source of pathogens, but I
>could be wrong.
Wild earthworms can cause a fatal protozoan disease called histomoniasis in
birds. Domestically raised earthworms have not been a problem. I don't
know about transmission of fish diseases (yet!)
I would only be feeding them live and was asking
>about their nutritional value.
I tried to get the same information 2 years ago, calling universities and
ardent insect hobbyists. I didn't get very far. I would love to see
what you come up with.
Donna Fezler@rhealiving.com
GCR
1620 Baldwin Road
Jacksonville, IL 62650
USA
(217) 243-7683, fax 245-2919
*Leading the world in Rhea Research and Product Innovation
*Inventor of the dietary supplement Rhea Extract
*Pioneering research on the role of environmental toxins in autoimmune
disorders
(web page temporarily offline while we change servers)
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Subject: RE: worms as fish feed
From: Mark Andrus
Date: Wed, 10 Dec 1997 10:20:25 -0500
Where are these messages coming from?
Mark M. Andrus
B. A. Mullican Lumber & Mfg. Co.
-----Original Message-----
From: GCR [SMTP:gcr@rhealiving.com]
Sent: Wednesday, December 10, 1997 4:21 AM
To: aquaponics@townsqr.com
Subject: Re: worms as fish feed
Earthworms, on
>the other hand, I've never considered to be a source of pathogens, but I
>could be wrong.
Wild earthworms can cause a fatal protozoan disease called histomoniasis in
birds. Domestically raised earthworms have not been a problem. I don't
know about transmission of fish diseases (yet!)
I would only be feeding them live and was asking
>about their nutritional value.
I tried to get the same information 2 years ago, calling universities and
ardent insect hobbyists. I didn't get very far. I would love to see
what you come up with.
Donna Fezler@rhealiving.com
GCR
1620 Baldwin Road
Jacksonville, IL 62650
USA
(217) 243-7683, fax 245-2919
*Leading the world in Rhea Research and Product Innovation
*Inventor of the dietary supplement Rhea Extract
*Pioneering research on the role of environmental toxins in autoimmune
disorders
(web page temporarily offline while we change servers)
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Subject: Interesting Introduction & Questions
From: S & S Aqua Farm
Date: Wed, 10 Dec 1997 13:34:07 -0600
To the list - Several days ago this introduction was posted. Many of our
current subscribers were not on line at that point, and I wanted to reissue
it for information and comments. Mr. Prentice has some very important
questions toward the end of his post, and we will endeavor to answer each
one as quickly as possible. Wanted to offer the opportunity for the rest of
you to comment if you wish. Perhaps between us we can get the job done.
Paula Speraneo
>Date: Tue, 02 Dec 1997 12:16:32 -0800
>From: "Lloyd R. Prentice"
>S & S Aqua Farm wrote:
>> We urge each of you to send a short introduction so that we can get a feel
>> for the needs of the group.
>
>Many thanks for organizing this forum.
>
>My name is Lloyd Prentice.
>
>Many years ago I visited New Alchemy in Falmouth, MA. The founders,
>Nancy and Jack? Todd, William McLarney, and others were, as I recall,
>former Marine Biology Institute (Woods Hole) scientists who had become
>tired of conducting a "death watch" on the oceans.
>
>New Alchemy raised Tilapia and various food and flowering plants in
>solar structures. Wind provided the pumping power. Their goal was to
>develop low cost, environmentally integrated, low-maintenance food
>production systems suitable for low-income and third-world families and
>communities. Their efforts, heavily subsidised by enthusiastic
>volunteers, centered around controlled experiments that were fairly
>rigorously monitored and reported. They produced a number of handsome
>publications. Last I checked New Alchemy had shut down its physical
>operations and was providing consulting services to municipalities
>concerned with better ways of managing effluents. I don't know if they
>published an ultimate finding regarding the feasibility/practicality of
>their food production efforts.
>
>I also visted Integral House in Berkeley. They had a bee hive over a
>fish pond to provide a protein source (dead bees) for their fish. I'm
>not sure if they were raising enough fish to make a serious contribution
>to either diet or income, but the concept of biologically integrated
>cultural systems really captured my imagination.
>
>I've long fantacized about creating and maintaining such a system for my
>own family, but my demanding business (editorial services and creative
>software development) has, over the years, soaked up most if not all of
>my discretionary time and money. Groundhogs torpedoed my efforts the one
>year I was able to get a garden started. The best I've been able to do
>is collect information as it's drifted my way. And each year I hope that
>maybe I can squeeze out enough time and energy to get started on a sound
>footing.
>
>Several years ago my nephew, with a fresh degree in agricultural
>management from Cal Poly, and with backing from my sister, started a
>30-acre aquaculture operation in northern California. His goal was to
>raise golden carp for the Chinese market in the San Francisco Bay Area.
>He'd done some amount of research before he started and had the guidance
>of several aquaculture professionals to draw on, including a biologist
>with many years of experience in aquaculture operations. The market was
>strong, willing to pay $3.00 or more per pound for his product.
>
>The property was a former catfish operation, so most of the
>infrastructure was in place. He cleared the brush, filled the ponds,
>shipped in a truckload of brooder fish from somewhere in the south, and
>started feeding massive quantities of expensive, high-class fish food.
>The first year he thought his only problem was birds, because the fish
>took to the ponds like fish to... well. Indeed they procreated like
>crazy. Into his second and third years, however, he began to realize
>that he had a serious problem. The fish were so busy eating and
>procreating that they they were neglecting to grow. He could get them up
>to three-quarters of a pound or so, but the market wanted one pound and
>larger. They were also back-breakingly difficult to catch, even with
>seine nets. But they did love to eat.
>
>My nephew was able to capture a small chunk of revenue by raising
>minnows and bass in a couple of his ponds. But the market was limited.
>One summer weekend, however, a week or so before he planned to harvest
>his annual bass crop, he decided to go hunting. The pump that raised
>water from his deep water well blew out an hour or two after he drove
>out the gate, stopping the flow of fresh aereated water into his bass
>ponds. By Sunday, when he returned, his $10,000 bass crop was floating
>on the surface of the ponds, seriously depreciated in value.
>
>Unfortunately, as a result of disappointment, guilt, and heavy financial
>losses, the aquaculture field lost a bright, energetic young man that
>day.
>
>I had urged my nephew, when he started the venture, to carefully list
>all the possible risk factors and to develop contingency plans. I'd also
>urged him to conduct some controlled experiments to develop a growth
>model for the specific fish he was trying to raise. But I think the
>enthusiasm of the new venture, and the back breaking effort once he got
>under way, kept him from thinking carefully and creatively about the
>venture.
>
>Sorry to go on so long, but I think the cautionary tale illustrates how
>important a forum like this can be in helping novices get off on the
>right foot. If my nephew had had a group like this to call on perhaps he
>could have avoided the obvious mistakes, or at least turned his
>operation around in time to avoid disaster. As it was, I think he was
>heavily influenced by commercial trade sources that were advocating an
>industrial model of fish production - every solution cost more money
>than he had. All he could understand once he got into trouble was to
>continue doing more of the same thing - feed the fish expensive ration
>and wait for them to grow. Aquaponics, it seems to me, forces focus on
>the total cultural environment. Am I right in assuming that it also
>forces you to walk before you run?
>
>Here are some of the questions, aside from time and money, that have
>stopped me from moving forward:
>
>1) What assumptions are necessary to create a reasonable cultural model?
>2) What assumptions are necessary to create a reasonable business model?
>3) Where can I find the most pertainent scientific knowledge to avoid
>making
> stupid mistakes?
>4) What's the minimum infrastructure needed to say,
> - supplement family diet
> - supplement family income
> - sustain a small business?
>5) In our Boston, MA, climate, does aquaculture really make sense at
>all?
>6) Are Tilapia the best fish to raise in our Boston, MA, climate?
>7) Where do you obtain Tilapia?
>8) How do you keep energy costs from killing you?
>9) Are there local, state, federal regulations that one must be aware
>of?
>
>I hope, as the discussion unfolds, that these are among the issues that
>will be tossed around. Here are some other questions:
>
>I have been reading about S&S Aqua for awhile now and it sounds like
>they have developed a practical cultural model...
>- How well does this model scale both up and down?
>- How well does it travel to other climates and conditions?
>- Who has alternative models? How do you evaluate competing ideas short
>of investing serious time and money?
>
>Hope you guys don't mind Micky the Dunce asking, perhaps, obvious (to
>some) questions. But its the best I can contribute to the group at the
>moment.
>
>Best wishes,
>
>Lloyd
------------------------------------
S&S Aqua Farm, 8386 County Road 8820, West Plains, MO 65775 417-256-5124
Web page http://www.townsqr.com/snsaqua/
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Subject: Re: Taste of my produce
From: S & S Aqua Farm
Date: Wed, 10 Dec 1997 13:41:40 -0600
At 03:31 PM 12/8/97 EST, you wrote:
>This is Peter Theisen again. Remember I have a small system where I use
>the water from the Tilapia tank to grow vegetables in a gravel bed under
My Question
>is: Why does my lettuce taste more bitter than that grown outside and why
>do my radishes come out so tasting so sharp?
Pete - I would agree with most of your responders that heat would be your
problem. Lettuces generally require a cooler temperature (or harvesting
sooner) to maintain flavor. We've have no bitter lettuces noted from the
system that hadn't been a direct result of trying to cut from them too long
(in our learning stage) or not harvesting soon enough in the warmer months.
What variety of lettuces are you growing. I'd be happy to pass along the
ones that have done well for us.
Paula
S&S Aqua Farm, 8386 County Road 8820, West Plains, MO 65775 417-256-5124
Web page http://www.townsqr.com/snsaqua/
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Subject: Open list discussions (was worms as fish feed)
From: S & S Aqua Farm
Date: Wed, 10 Dec 1997 13:54:20 -0600
At 10:20 AM 12/10/97 -0500, you wrote:
>Where are these messages coming from?
The subject came up when discussing various options on raising red wigglers
in a greenhouse vermicomposting system. The discussion then led to
potential of using the worm "crop" to supplement feed the fish "crop", I
believe.
With almost 200 subscribers to this list, many not in the U.S., where
economics and feasibility of such a system as ours runs into unthought of
obstacles, I believe we should encourage the exploration of all topics
toward that end. We're trying to find alternative feed sources in Europe
right now to bring the system operating costs more in line with the
economics of Romania.
Any topic may be and should be discussed. In order to bring the topics into
the areas you want, we encourage everyone to post their queries,
observations, comments and suggestions for how this type integrated system
should, does or might work.
Paula Speraneo
S&S Aqua Farm, 8386 County Road 8820, West Plains, MO 65775 417-256-5124
Web page http://www.townsqr.com/snsaqua/
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Subject: Re:Tilapia Water Temperature & Nutrient Level
From: S & S Aqua Farm
Date: Wed, 10 Dec 1997 17:32:30 -0600
At 04:18 PM 12/9/97 -0600, you wrote:
>Paula- What temperatures due you maintain your tilapia at during winter
>and summer? When the temp falls in the winter I assume you reduce feed
>which will result in a drop in nutrient levels for your plants. Do you
>adjust your winter crop choices accordingly, growing more lettuce and
>fewer tomatoes, for example?
> Also, what sort of health problems have you encountered which you
>attribute to high water temps? I know that DO levels drop as temp rises
>and that ammonia can do the same, both of which can lower the fish's
>resistance and encourage disease. But are you seeing certain diseases
>directly caused by higher temps? I understand that T. nilotica is one of
>the commonly cultured species which is known to tolerate lower temps.
> Regards, Gordon
>
> & S Aqua Farm wrote:
>>
>> There are many different varieties of Tilapia, with different temperature
>> tolerance levels. Although that is the desired water temperature for
>> maximum growth, it also can contribute to fish health problems, as well as
>> increase cost of operation. We don't maintain that temperature through the
>> winter, and accept a slower rate of gain for the fish in exchange for
>> maintaining nutrient levels sufficient to continue our crops (which are the
>> product with the quickest turn in our system).
>>
>> Paula Speraneo
Gordon -
Our winter temperatures vary by the day - depending on sunlight. Air temp
(and water temp) will fall during long periods of cloudy days, and both will
climb on sunny days. We don't add extra heat to the greenhouse or water
unless water temp drops to dangerous levels for the Tilapia (under 55
degrees F.), then we only heat the water with electric heaters sufficient to
stabilize until the sun reappears. We've tried to gear our crops to close
to natural seasons to take advantage of this method. If your end market
warranted, I'm certain there are sufficient reasons to add heat and light to
increase air temp and extend "sun" hours.
Actually we have a couple of tomato varieties which thrive in cooler
temperatures, and we don't have to completely change over crops, just be
certain to have the correct varieties for these winter months.
As for nutrient levels - We don't expect a slower rate of growth in our grow
beds just because we slow up feeding the fish. Because we're using a
natural nutrient source (fish waste and excess fish food), our nutrients are
not necessarily "plant ready" when they enter the system. Excess food and
fish waste solids are slowly broken down by the bacterial system into
nutrients available for plant uptake. I've often likened this to growing
plants in a constantly rejuvenating compost pile - always new raw nutrients
being input, while available nutrients are being taken out.
The fact that the plants utilize enough to clean the water for the fish is
and has always been amazing to me.
As to health problems with fish, we have had none other than some loss when
we did not heat the water at all. My reference applied to our experience
raising ornamentals years ago, when proper water temperature in aquariums
was maintained, only to find that it was also the "opportune" temperature
for diseases common to them - ich, hole-in-the-head, etc. We've not
experienced any of them in our system. We've contributed that to the fact
that Tilapia are extremely hardy and disease resistant, but perhaps the
overall health of the system contributes also.
Paula
S&S Aqua Farm, 8386 County Road 8820, West Plains, MO 65775 417-256-5124
Web page http://www.townsqr.com/snsaqua/
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Subject: Extruders
From: S & S Aqua Farm
Date: Wed, 10 Dec 1997 18:19:51 -0600
To the list - following received from Bob Leader, referred by Steve Bonney,
as a reference for extruders used in producing fish feeds. Hope this
information is usable to those who are interested.
Paula Speraneo
>Date: Wed, 10 Dec 1997 18:21:44 -0500
>From: Bob Leader
>To: snsaquasys@townsqr.com
>You wrote:
>Bob - Did you wish the information on your site forwarded to the group?
>I'd be glad to post if you wish.
>
>Would you, please?
>We are involved in feeding crustaceans with work being done at Purdue,
>Univ. of Maine, and the Univ. of the West Indies in Jamaica. But we
>also are working with many small independent operations in the U.S. that
>have small extruders. Steve Bonney's been passing on some of the
>conversations you've been having about this equipment, and I thought I
>could help. We do not sell equipment, but can share the names of
>companies that do.
>Bob Leader
Earlier references show:
-----------------------------------
I am presidnet of a group of independent extruder/press operation in the
U.S. known as Producers' Natural Processing Inc. While we don't sell
extruders and oil presses, we have been able to come up with equipment
sources.
See http://www.pnpi.com
Thanks,
Bob Leader
-----------------------------
S&S Aqua Farm, 8386 County Road 8820, West Plains, MO 65775 417-256-5124
Web page http://www.townsqr.com/snsaqua/
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| Message 11 |
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From: Mark McCormick
Date: Wed, 10 Dec 1997 22:06:00 -0500
set-digest
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| Message 12 |
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Subject: economics/sustainability of production
From: Jack Rowe
Date: Thu, 11 Dec 1997 00:04:37 -0500
On 12/10/07, Paula Speraneo wrote:
"With almost 200 subscribers to this list, many not in the U.S., where
economics and feasibility of such a system as ours runs into unthought of=
obstacles, I believe we should encourage the exploration of all topics
toward that end. We're trying to find alternative feed sources in Europe=
right now to bring the system operating costs more in line with the
economics of Romania."
I agree wholeheartedly! Economics of production is an extremely pertinent=
topic in these days when ecosystems and resource bases are under serious
threat. In the USA, the energy which goes into producing farm-raised
catfish FAR exceeds the energy which can then be gotten from the fish. Th=
is
seemingly impossible situation is made possible by fossil fuel inputs in
the form of commercial food production and processing, aeration, water
pumping, pond materials production, etc., etc. =
In many -- probably most -- parts of the world, putting more into a food
production system than can be gotten out is simply not possible. Dan
Hemenway's interesting comments about the caloric impracticality of feedi=
ng
good meat to fish and the practice of feeding maggots to fish are not
considered unrealistic in Asian fish production systems. In Asia, fish
ponds receive much of their necessary phosphorous and calcium from animal=
,
human and bird manures, with animal pens and even latrines placed where
effluents reach the shallow, low-trophic (phyto- and zoo-plankton
producing) areas of fish ponds. Economically-important carp have evolved =
in
concert with dense human populations to survive in polluted waters with
very low dissolved oxygen levels in which catfish, for example, could not=
survive. Carp exist for highly-efficient production of food from every
trophic level in a pond, from vegetation-eaters to plankton-eaters to
carnivores (the common bass/bluegill/catfish trio is our southern-US
trophic-ladder equivalent, though vegetation is, sadly, not well-utilized=
by this group). =
In Europe, also, many alternative ways of maintaining the aquatic food
chain are practiced, including fertilization with animal and vegetative
'manures'. Ponds are commonly drained during winter months and planted wi=
th
edible crops or green manures to reclaim excess nutrients from bottom mud=
(the practice of drying pond bottoms can be quite beneficial to pond
health, helping to control many parasites and diseases of fish). In easte=
rn
Europe especially, economics of production dictates that energy out excee=
ds
energy in, and Paula mentions efforts to adapt scientific production
methods to the extremely 'earthed' economy of Romania. =
These approaches to production, far from being crude, are far more
'scientific' than our methods of producing 100 calories of fish (or corn,=
or beef) with several hundreds of calories of high-protein food and energ=
y.
It doesn't take a calculator, a slide rule or even an abacus to figure ou=
t
putting more energy into a system than comes out is a failure of sorts,
even if the fish tastes great fried in cornmeal. Using vermiculture syste=
ms
to convert human food wastes into high-quality terrestrial fertilizer AND=
nutritious fish food, all in one fell swoop, is an excellent move toward
sustainability of production. Cleaning polluted water by using it to wate=
r
and fertilize terrestrial crops is another good idea. =
John Todd was mentioned in connection with water purification by biologic=
al
means, and his book "Living Machines" discusses this idea in depth.
Dwelling-size waste-purification systems turn out extremely high-quality
water and produce significant amounts of vegetables and fish.
An excellent, science-based fish farming resource which outlines intensiv=
e
US fish production methods as well as alternative, low-input,
highly-productive fish raising methods as practiced in Asia and Europe is=
"Textbook of Fish Culture: Breeding and Cultivation of Fish" by Marcel
Huet, published by Fishing News, London, 1972. To me this is a "must-read=
"
for anyone wanting to establish a sustainable fish production system.
I'm really enjoying the expertise and provocative, innovative questions a=
nd
ideas from of the members of the list, thanks! Who were the 'crackpots'
yesterday are the visionaries tomorrow!
Jack Rowe
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