Aquaponics Digest - Thu 09/16/99
Message 1: Re: ozone generators
from "Sam Levy"
Message 2: Re: ozone generators
from Dave Miller
Message 3: Re: ozone generators
from Mike Strates
Message 4: Re: small family set up
from Jim Sealy Jr
Message 5: Re: small family set up
from Jim Sealy Jr
Message 6: Re: Pictures/attachments, was Re: Root Crops
from
Message 7: Re: Re: Re: I want to join your discussion group
from
Message 8: Re: Trout dietary needs
from
Message 9: Re: small family set up
from
Message 10:
from
Message 11: Re: ozone generators
from Marc & Marcy
Message 12: Nutrient and water uptake
from Ronald Polka
Message 13: Re: Nutrient and water uptake
from "William Brown"
Message 14: floating raft tables
from Adriana Gutierrez & Dennis LaGatta
Message 15: Re: Nutrient and water uptake
from "William Brown"
Message 16: Re: ozone generators
from "Frank Stancato"
Message 17: Re: floating raft tables
from "William Brown"
Message 18: Re: ozone generators
from Mike Strates
Message 19: Re: ozone generators
from "Jewel Lopez"
Message 20: Re: Nutrient and water uptake
from "Jewel Lopez"
Message 21: Re: floating raft tables
from Adriana Gutierrez & Dennis LaGatta
Message 22: dissolved oxygen DO Re: ozone generators
from William Evans
Message 23: tilapia origin
from "Wendy Nagurny"
Message 24: Re: floating raft tables
from "William Brown"
Message 25: Re: Pictures/attachments, was Re: Root Crops
from "Jewel Lopez"
Message 26: Re: Re: Trout dietary needs
from "Jewel Lopez"
Message 27: Re: Re: small family set up
from "Jewel Lopez"
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| Message 1 |
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Subject: Re: ozone generators
From: "Sam Levy"
Date: Wed, 15 Sep 1999 22:01:04 PDT
jay--
you might want to check out your local safety requirements before
configuring in an ozone generator. also consider you configuration
carefully as adding ozone to culture water is ver similar to pouring in
bleach in many respects.
sam
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Subject: Re: ozone generators
From: Dave Miller
Date: Thu, 16 Sep 1999 01:04:33 -0400
Sam,
How is the ozone generation dangerous? Somehow I assumed it was
beneficial. I know oxygen is an accelerant for fire. How are these
related or different?
recycler dave
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| Message 3 |
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Subject: Re: ozone generators
From: Mike Strates
Date: Thu, 16 Sep 1999 18:50:48 +1000
On Thu, Sep 16, 1999 at 01:04:33AM -0400, Dave Miller wrote:
> How is the ozone generation dangerous? Somehow I assumed it was
> beneficial. I know oxygen is an accelerant for fire. How are these
> related or different?
Ozone is a poison. Its the reason why your eyes itch and your sinuses play
up after a thunderstorm. Airborne ozone can cause problems with your lungs,
or even unconciousness in large enough doses. Remember, oxygen is O2 --
ozone is O3... there IS a difference.
--
Mike "Skyfox" Strates ; www.croftj.net/~mstrates
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Subject: Re: small family set up
From: Jim Sealy Jr
Date: Thu, 16 Sep 1999 05:52:06 -0500
Mike,
Check with the local auto supply stores who mix paint. Most have changed
over to using digital scales in the last couple of years and you can
probably pick up one of the old shadowgraph scales for little or
nothing. These are accurate to .1 gram and work in the weight range
needed for checking fish growth. I use an Ohaus digital meant for the
same purpose and love it. Just put a bucket of water on the scale, zero
the reading (same as when mixing paint), then add your fish. I also
still have the old shadowgraph I used for about 20 years before that and
there's really not anything to wear out on it. It just doesn't have a
port to hook into the computer for recording weights. This method won't
overly stress the fish and you can weigh even the smallest fry fairly
safely. Always remember to re-zero the scale between fish if you're
checking several samples, otherwise your fish will get progressively
heavier for some strange reason. ;) Nah, I've never _really_ done that..
Honest!.
At 55 gallons, your tank is just about the perfect size to use an inline
heater intended for maintaining the block temp on an auto engine. These
can also be picked up fairly cheaply at most auto parts stores (and
junkyards), just don't place all your trust in the thermostat on one
from the junkyard. I've used water heater thermostats with good results
over the years.
Can't help much on where to find barley straw, but I've tried wheat
straw and found it works also. I've seen it available as bedding where
horse supplies are sold around here.
Jim Sealy Jr.
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Subject: Re: small family set up
From: Jim Sealy Jr
Date: Thu, 16 Sep 1999 05:58:15 -0500
You'd never guess I was behind on reading the forum, huh?
Jim Sealy Jr wrote:
>
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Subject: Re: Pictures/attachments, was Re: Root Crops
From:
Date: Thu, 16 Sep 1999 7:47:18 + 5 EST
sounds good here, too!
Mike
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Subject: Re: Re: Re: I want to join your discussion group
From:
Date: Thu, 16 Sep 1999 7:50:02 + 5 EST
Yeah, that is snow!!! We average about 120-150 inches per year throughout
the season.
Sources for trout..... Not much around your neck of the woods i am familiar
with. We get most of
ours from the Dept of Environmental Conservation here in NY - they are more
than willing to give us
a couple hundred every year!
Mike
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Subject: Re: Trout dietary needs
From:
Date: Thu, 16 Sep 1999 8:10:55 + 5 EST
Jewel,
Trout are mainly supplied in nature by macroinvertebrates such as stone
flies, small crustaceans,
and the many insects that hang out in and near water. (this includes
crickets, g-hoppers, ants,
etc...) Larger trout have been known to take small mice, large minnows and
in some cases other
game fish (yes, including other trout).
In recircultaing aquaculture systems, trout are usually fed a high fat ,
high protein (+/- 40%) trout
food relative to their mass and overall size. Most Trout will start on a
small crumble(almost granular
like coffee and appropriate for fish up to about 3 inches) and then the size
of the food is increased
to as large as 1/4". The most entertaining thing is that it seems innate
for them to take earthworms,
as well. My students thoroughly dangling a worm over the tank. Trout have
great vision above
water, also, and strike the worm and take it right out of the hand of the kids.
Watch what you feed!!! Cheap food is usually just that - CHEAP. Make sure
you get quality stuff
(Zeigler, Hikari, etc...). Cold store your feed and use it up within about
6 months. DO NOT LET IT
GET WET (odd, since it gets wet when in use). You will end up with a 50
pound block of solid food
if the humidity/water content increases too much. Also, for clearer water,
consider running it
thtough a screen sieve to shake out any fine powder. This can reek havoc
with your bacterial
colony/biofiltration system.
We feed this food to our tilapia and our trout. Growth rates increase
dramatically. I would
reccommend visiting Aquatic Ecosystems http://www.aquatic-eco.com. They
have a FANTASTIC
tech support site and the people there are quite helpful (look for my letter
in the front of the
catalog, unless they have taken it out - page 2).
Hope this helps!
Mike
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| Message 9 |
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Subject: Re: small family set up
From:
Date: Thu, 16 Sep 1999 8:17:18 + 5 EST
Mike,
You can get Barley straw from "Aquatic EcoSystems" in Apopka, FL (although
they may be shut
down for Floyd right now. They have it in stock as well as a great little
"tech-talk" section regarding
its use. They sell 1/2 pound for $6.95 - Item #BST5. They are located at
http://www.aquatic-eco.com
or
aes@aquaticeco.com
or
1-800-422-3939
Mike
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| Message 10 |
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Subject:
From:
Date: Thu, 16 Sep 1999 10:59:48 + 5 EST
Tilapia Question.....
We are designing a student run experiment on the following - any thoughts?
We have discovered that when we feed sinking food to our tilapia, the feces
that they produce
seems to float to the surface. HOWEVER, when we feed floating food, the
feces tends to sink. Is
there a correlation that anyone can give us background information on?
Mike
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Subject: Re: ozone generators
From: Marc & Marcy
Date: Thu, 16 Sep 1999 09:11:09 -0600
> Some ozone systems use UV lights (sometimes called
> "blacklights"). You can find the florescent UV tubes all over, I've seen
> them at some walmarts, and you can get a complete 18" unit with fixture from
> those Spencer gift shops that are in most big malls. It would just be a
> matter of putting it into a little box, then using an aquarium air pump to
> take the air from there, and bring it into the water as usual.
Won't work. Don't waste your money. The "black lights" sold
for decorative purposes are not designed to put out ozone.
The bulbs used to generate ozone are around 50 to 90 dollars
and will damage your eyes if you look at them too long.
Entire units cost well over a thousand dollars for a cheap
one that really works.
I suggest you refer to:
http://www.atlanticuv.com/sterlray/index2.htm
You can note the safety information for ozone on the above
web site.
The water treatment industry in the USA IS NOT REGULATED
WELL SO BUYER BEWARE when it comes to sales claims about
safety. Ozone is a poison no matter what irresponsible ozone
purification vendors claim. It is not as "safe, fresh and
natural as nature". Ozone is as "dangerous, fresh and
natural as any other natural oxidizer".
Proper ventilation is essential for safety, especially for
home-brew systems where you don't know how much residual
ozone you have.
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Subject: Nutrient and water uptake
From: Ronald Polka
Date: Thu, 16 Sep 1999 10:20:20 -0600
Greetings all
I am looking for information relating to the water and nutrient uptake
rates for floating raft systems that cultivate bibb type lettuce. What is
most important is the total usage of water and nutrients in the complete
culture cycle. Does anyone know of published papers or other data relating
to this? TIA
Ron Polka
Southwest Technology Development Institute
New Mexico State University
Box 30001, Dept 3SOL
Las Cruces, NM 88003
rpolka@nmsu.edu
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Subject: Re: Nutrient and water uptake
From: "William Brown"
Date: Thu, 16 Sep 1999 08:08:57 -1000
I have 10 floating raft tables in commercial production. They're great,
easy to work with and I get a 10F lower temperature on hot days compared to
white plastic covered tables. I put a piece of 1x2 inch lumber on each side
so the raft is suspended when the nutrient solution is consumed. This
allows to the roots to hang and absorb more oxygen. I grow leaf lettuce
which I calculate (by experiment) use 1 gallon of water/lettuce upto .66lbs.
I would expect that Bibb lettuce is similar if you adjust for the smaller
size/weight.
For nutrient we assume a lettuce is 95% water. When dried and analysed the
5% organic matter is approx 3.5% nitrogen. (per Dr. B A Kratky,
Non-circulating Hydroponic Metthods available at HSA library). We add
nutrient based on the NPK to solution to allow 3.5% nitrogen/plant
So .66lbs = 10.5oz lettuce x 5% dry matter = .525oz dry matter x 3.5%N =
.018oz N/gallon water for each lettuce. I use a lettuce fertilizer with
8%N. So 1oz nutrient = .08oz N and .018/.08 = 1/4oz nutrient/gallon water
for each lettuce. Theoretically you would end up with no leftover water or
fertilizer, alas life is not so perfect.
My experience has been it is better to just keep the pH at 6.2 and the EC at
1.8 (red lettuce should be lower, 1.5EC). I know some people will have
different EC suggestions but for our conditions and setup an EC of 1.8 is
best.
William Brown mahiwai@cmpmail.com
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Subject: floating raft tables
From: Adriana Gutierrez & Dennis LaGatta
Date: Thu, 16 Sep 1999 14:15:09 -0400
William,
Can you tell us a little bit about your tables? How are they
constructed and how do they operate? Thanks.
Adriana
> I have 10 floating raft tables in commercial production.
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Subject: Re: Nutrient and water uptake
From: "William Brown"
Date: Thu, 16 Sep 1999 08:23:55 -1000
Forgot to mention that the Knott's Handbook for Vegetable Growers has a
table that lists water content, nitrogen and various other composition
elements for most vegetables.
William Brown mahiwai@cmpmail.com
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Subject: Re: ozone generators
From: "Frank Stancato"
Date: Thu, 16 Sep 1999 15:04:14 -0400
Jay, my understanding about ozone (O3) was that it was used for sanitary
reasons and not as an oxygen (O2) supplement.
Has anyone ever tried using the old chem lab experiment? A low voltage
current passed through water will produce O2 and H2. I can not for the life
of me remember which terminal produces which gas. If you vent the H2
(exposive) you should have no trouble.
Frank
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Subject: Re: floating raft tables
From: "William Brown"
Date: Thu, 16 Sep 1999 09:27:43 -1000
My raft tables are constructed with 2x4 lumber with dimesions 3x12 feet
which let me put 48 lettuce in each table. The bottom is used corrugated
roofing nailed to the lumber. This table is then rested on top of 4x4 inch
lumber installed as supporting legs. Some people build the table legs and
nail the roof iron to the legs and lay the lumber frame on the roof iron.
Each table is lined with 6mil plastic from the hardware store. Before
laying the plastic I add a 1x2 inch length of lumber along the sides inside,
this holds the rafts up with the some of the roots exposed to the air when
the nutrient solution goes down giving the lettuce more oxygen when they
need it most at maturity and high temps. I purchase 2x6 foot foam sheets
(made for rafts) from a local distributor which I cut 2 inch holes in spaced
1 foot apart (approx). I lay these on the plastic covered 1x2s and fill
the table with water. In the holes I use 2 inch net pots which extend into
the nutrient solution and hold the lettuce. I place the lettuce seedling
plugs from a 98 cell plastic tray in the net pots without additional media.
Makes cleaning and replanting a quick and painless process. I like to grow
the seedlings as large as possible, in my case 2-3 weeks depending of the
weather. At this time the roots bind the Sunshine Mix #5 mixed with coco
fiber together and will pop out of the tray with a careful tug. In the
summer I will have to add water because of the higher transpiration, but
during winter I generally don't need to adjust anything. I use nutrient
injectors to combine the nutrient with the water at the time I fill the
tables with water. Our water is highly acid and I occasionally have to
adjust pH but generally I just let the nutrient buffer the solution.
The floating raft system is significant in reducing solution temperature for
those of us living with high summer temperatures. I mentioned 10 degrees F.
What I didn't mention is that the plastic covered tables will get temps in
the 90s while the highest the raft tables have been is 81 degrees F. A
great way to ward off oxygen problems. I may even add fish again to eat the
mosquito larvae. In the past the summer heat would kill of the little fish.
I was using guppies.
I never empty the solution from the table, I just fill them up again.
Contrary to some contemporary notions this setup has been in production for
over seven years and produces extremely fine lettuce. Occasionally the
nutrient chemistry does get out of wack, usually if I get a pest infestation
or the day/night temps are too high or close to equal and the lettuce
doesn't grow right, then I will empty the table and refill to get things
back in balance and the lettuce will green up. The lettuce will look a
little yellow telling me it's time to fix things up. It's not unusual to
have a table go 1 to 2 years without being flushed.
If I missed anything get back to me.
William Brown mahiwai@cmpmail.com
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Subject: Re: ozone generators
From: Mike Strates
Date: Fri, 17 Sep 1999 07:48:57 +1000
On Thu, Sep 16, 1999 at 03:04:14PM -0400, Frank Stancato wrote:
> Jay, my understanding about ozone (O3) was that it was used for sanitary
> reasons and not as an oxygen (O2) supplement.
You're completely correct. Ozone is used as a disinfectant, and would be
useful for cleaning water (possibly in a marine aquaculture setup) but not
good for anything else. It is my personal opinion that O3 is too dangerous
for home aquaculture use.
> Has anyone ever tried using the old chem lab experiment? A low voltage
> current passed through water will produce O2 and H2. I can not for the life
> of me remember which terminal produces which gas. If you vent the H2
> (exposive) you should have no trouble.
What you're talking about is electrolysis. Electrolyzing H2O will indeed
give you H2 and O2, but you forgot one important product -> heat. Because of
this heat, you waste a HUGE amount of energy in making the oxygen, which
you'll never reclaim, even if you burn the hydrogen in an engine. This would
be completely inappropriate for those without access to a several kW free
energy source (ie: most people).
There is hope, however. If you want to supply the fish with pure oxygen, you
could use two systems which can be made at home. To make the first, you'll
need two large water cooler bottles (you know the blue plastic ones).
The idea is that you drill a hole in the caps of the cooler bottles to fit
some cheap garden hose and that you glue the garden hose in with a STRONG
reliable glue. The first cooler bottle needs to be filled around half way
with 30% hydrogen peroxide (this is nasty stuff; be careful...) and mounted
somewhere high... perhaps on a stand of bricks of milk crates or hung from
the roof.
The second cooler bottle sits low and the bottom of the bottle is filled
with around 4lb of maganese dioxide. Drill a hole in the side of the cooler
bottle (ABOVE HALF-WAY, duh! you don't want H2O2 going in the water... so
choose a level which is higher than what the large tank is filled to, get it?)
and glue some airline in.
Cut the hose going from the large bottle to the smaller bottle and insert an
inline regulator tap. Run the airline to the bottom of the aquaculture tank.
Depending on how fast you let the peroxide DRIP into the lower tank, is how
much O2 you'll get. Typically, you'll get 100L of pure O2 gas out of 1L of
30% H2O2 (100 vol, I think.) That's the eqv. of 500L of normal air!
So, what that means is that with 25L of 30% H2O2 (not that expensive) you
can make 2500L of pure O2... that's 12,500L of normal air!!!
The other idea is to use Nitrox gels which are used to fill scuba tanks --
they can increase the O2 content in the air by using a selective membrane.
These need a powerful compressor, though. Comments? -Mike
--
Mike "Skyfox" Strates ; www.croftj.net/~mstrates
Voice: (011) 613-9440-5778; Voicemail (US): 1-888-392-4832, ext: 2913058153
ICQ #47663425
"... and while you're at it, why not treat the pax to some zero
G's. Just knock the yoke right down the stoppers with one hand,
and after you've made a perfect recovery, advise all on board
that this terrible mishap was a result of clear air turbulence"
-- Mike's 101 Never-Fail Ways to get fired from United.
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Subject: Re: ozone generators
From: "Jewel Lopez"
Date: Thu, 16 Sep 1999 13:53:20 -0600
That's true to an extent, too much concentration of it is a health hazard,
however it does
have many uses in the right amount. In the air, the right amount makes it
smell like a fresh summer day, too much makes it smell like bleach (which it
is similar to). But like I said earlier, I don't know how it would do with
fish. It does go away fast though, and we will be using well water that was
previously treated with it, both for drinking and our fish/crops. We had
one for our boat to kill
mold and other foul "boat odors". It purifies water. It actually
eliminates odors rather than masking them. We used to run it when the kids
had a cold because it kills bacteria and virus' in the air, and it helped
keep the rest of the family from getting it. Many hotels use units now, to
get rid of odors, including turning a "smoking room" into a "non-smoking
room" in a half hour of running it. We have a mild 12v cigarette lighter
plug model that we use in the car now for driving in smog, getting rid of
odors, etc.. Again, it is being used for well water
storage tanks to both eliminate fungus, bacteria, algae, etc., and even get
rid of chemical and metal contaminations. Outside of the US it's even being
used for medical treatments. You can buy those ozone well water purifiers
from the American Tank Company.
----- Original Message -----
From: Mike Strates
To:
Sent: Thursday, September 16, 1999 2:50 AM
Subject: Re: ozone generators
> On Thu, Sep 16, 1999 at 01:04:33AM -0400, Dave Miller wrote:
>
> > How is the ozone generation dangerous? Somehow I assumed it was
> > beneficial. I know oxygen is an accelerant for fire. How are these
> > related or different?
>
> Ozone is a poison. Its the reason why your eyes itch and your sinuses play
> up after a thunderstorm. Airborne ozone can cause problems with your
lungs,
> or even unconciousness in large enough doses. Remember, oxygen is O2 --
> ozone is O3... there IS a difference.
>
> --
>
> Mike "Skyfox" Strates ; www.croftj.net/~mstrates
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Subject: Re: Nutrient and water uptake
From: "Jewel Lopez"
Date: Thu, 16 Sep 1999 13:54:47 -0600
In case this helps at all, I heard of a system like that being used in a
japanese supermarket.
----- Original Message -----
From: William Brown
To:
Sent: Thursday, September 16, 1999 12:23 PM
Subject: Re: Nutrient and water uptake
> Forgot to mention that the Knott's Handbook for Vegetable Growers has a
> table that lists water content, nitrogen and various other composition
> elements for most vegetables.
> William Brown mahiwai@cmpmail.com
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Subject: Re: floating raft tables
From: Adriana Gutierrez & Dennis LaGatta
Date: Thu, 16 Sep 1999 17:38:21 -0400
William Brown wrote:
Thanks William,
How deep is your nutrient solution, about 3"? It appears that your
stryrofoam doesn't actually float on the surface but, rather, sits above
it supported by the 1x2" lumber?
Before
> laying the plastic I add a 1x2 inch length of lumber along the sides inside,
> this holds the rafts up with the some of the roots exposed to the air
Do you have a float valve to keep the right level? I have read that if
you add water above the previous level you would kill the roots.
> In the
> summer I will have to add water because of the higher transpiration, but
> during winter I generally don't need to adjust anything. I use nutrient
> injectors to combine the nutrient with the water at the time I fill the
> tables with water.
You just top up the tables, never dump the old nutrient?
> I never empty the solution from the table, I just fill them up again.
> have a table go 1 to 2 years without being flushed.
Thanks for sharing. This confirms the experience of one of our
extension offices. They set up a float system and the original batch of
nutrient was adequate until harvest. I've wanted to try this out, it
seems simple enough.
Adriana
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Subject: dissolved oxygen DO Re: ozone generators
From: William Evans
Date: Thu, 16 Sep 1999 17:17:21 -0700
Why make O2 when there's plenty all around..., I assume were talking
bout bringing up the DO (O2) content in the water, and not about
sanitation w/ O3. Either a pump system w/ a pressurized discharge onto
the water surface, or some type of mechanical agitator sitting on the
surface, or other designs that introduce the ambient air into water
circulating in a system.
billevans
Mike>
> There is hope, however. If you want to supply the fish with pure oxygen, you
> could use two systems which can be made at home. T
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Subject: tilapia origin
From: "Wendy Nagurny"
Date: Thu, 16 Sep 1999 22:43:36 -0400
I was wondering (and perhaps it was already mentioned here, but I forgot)
what country raises the tilapia filets we purchase in our grocers deli?
Since tilapia culture is restricted or tightly regulated in most states, I
presume that the bulk of what is available now in the US, is imported. From
where?
Wendy
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Subject: Re: floating raft tables
From: "William Brown"
Date: Thu, 16 Sep 1999 17:00:31 -1000
----- Original Message -----
From: Adriana Gutierrez & Dennis LaGatta
To:
Sent: Thursday, September 16, 1999 11:38 AM
Subject: Re: floating raft tables
>
> William Brown wrote:
> Thanks William,
>
> How deep is your nutrient solution, about 3"? It appears that your
> stryrofoam doesn't actually float on the surface but, rather, sits above
> it supported by the 1x2" lumber?
Floats at first until the last 2" of nutrient is used, then roots hang in
the air, just a mod to improve oxygen intake, I know of instances where
floating is all the way down.
>
> Before
> > laying the plastic I add a 1x2 inch length of lumber along the sides
inside,
> > this holds the rafts up with the some of the roots exposed to the air
>
> Do you have a float valve to keep the right level? I have read that if
> you add water above the previous level you would kill the roots.
No float valve and haven't killed enough roots to matter. In fact when I
want to slow growth down for a few days to match market timing I'll overfill
a table without injuring the lettuce.
> > In the
> > summer I will have to add water because of the higher transpiration, but
> > during winter I generally don't need to adjust anything. I use nutrient
> > injectors to combine the nutrient with the water at the time I fill the
> > tables with water.
>
> You just top up the tables, never dump the old nutrient?
Correct.
> > I never empty the solution from the table, I just fill them up again.
> > have a table go 1 to 2 years without being flushed.
>
> Thanks for sharing. This confirms the experience of one of our
> extension offices. They set up a float system and the original batch of
> nutrient was adequate until harvest. I've wanted to try this out, it
> seems simple enough.
There are a few of us here and the Japanese use floating rafts quite
extensively with good effect.
If you want to insure a single original batch of nutrient solution use 6"
high sides instead of 4". I used 4" originally so I could set containers on
the table bottom, with rafts it lends itself to greater depth. We found
that the extra depth was useful in keeping the temperature lower since there
is more room for the thermal energy to be absorbed. I have used 1x4 lumber
a couple times with adequate results, use 2x2 in the corners for secure
attachment of the sides.
>
> Adriana
>
William Brown mahiwai@cmpmail.com
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| Message 25 |
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Subject: Re: Pictures/attachments, was Re: Root Crops
From: "Jewel Lopez"
Date: Thu, 16 Sep 1999 18:59:10 -0600
Paula, that makes perfect sense to use your website for that project. Do
you want everyone to start sending their info and pics to you?
>
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| Message 26 |
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Subject: Re: Re: Trout dietary needs
From: "Jewel Lopez"
Date: Thu, 16 Sep 1999 19:06:32 -0600
----- Original Message -----
From:
To:
Sent: Thursday, September 16, 1999 2:10 AM
Subject: Re: Trout dietary needs
> as well. My students thoroughly dangling a worm over the tank.
Thanks Mike. Do you think the trout could live on earthworms alone? We are
shooting for as sustainable a system as possible, and growing worms for all
their dietary needs would be great.
Jewel
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| Message 27 |
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Subject: Re: Re: small family set up
From: "Jewel Lopez"
Date: Thu, 16 Sep 1999 20:38:47 -0600
There's a search engine for farmers that have all kinds of straw/hay. MUCH
less expensive but you have to catch it at the right time of year. Now may
still be good.
www.hayexchange.com
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