Aquaponics Digest - Tue 05/22/01
Message 1: Re: Fish Hatchery
from "F.Carl Uhland"
Message 2: Re: Aquaponics Digest - Sun 05/20/01-ORCHIDS
from DAVEINBHAM 'at' aol.com
Message 3: 05/20/01-ORCHIDS
from fishmanbruce 'at' webtv.net (Bruce Schreiber)
Message 4: Re: Aquaponics Digest - Sun 05/20/01-ORCHIDS
from Peggy & Emmett
Message 5: Re: Fish Hatchery
from fishmanbruce 'at' webtv.net (Bruce Schreiber)
Message 6: Re: Tilapia growth
from fishmanbruce 'at' webtv.net (Bruce Schreiber)
Message 7: Re: Marketing Tips?
from dreadlox 'at' cwjamaica.com
Message 8: email address change
from "Virginia Gilmore"
Message 9: RE: Tilapia growth
from "Carlos Arano"
Message 10: Israeli Innovations Slam Dunk It Again
from "TGTX"
Message 11: Oy Vey!!
from "STEVE SPRING"
Message 12: "Giving Up!"
from "STEVE SPRING"
Message 13: Re: Oy Vey!!
from marc 'at' aculink.net
Message 14: Re: Working with Fiberglass
from "David Atkinson"
| Message 1
Subject: Re: Fish Hatchery
From: "F.Carl Uhland"
Date: Tue, 22 May 2001 10:00:35 -0400
Hello Ted,
You gotta be careful of of some of the fridge liners as tanks. They=20
sometimes will have antifungal properties that are dangerous for fish.
Carl
At 18:48 21-05-01 -0500, you wrote:
> > The most daunting area to me is not necessarily the physical design but
> > the "harvesting" of the fry
. for best efficiency
and Im thinking
> > seeeeriously of how to plumb so as not to get a big mixup of poop and
> > fry or eggs.> > Any ideas??
> > Regards
> > Mike,
> > JAMAICA
>
>Hey, Mike
Que Pasta? How's life in sunny Jamaica?
>
>Anyway, have you thought of using old bathtubs or refrigerator liners as
>brood stock tanks, or should I say spawning tanks
.?
You know, maybe
>100-200 gallons in semi-rectangular or semi-cylindrical tanks that sit
>stably on the floor, and you can easily walk around such a tank size and
>harvest the fry if the brood fish expels them, or you can more readily net
>the broodfish up and isolate it into a 30-50 gallon Rubbermaid tub,
.etc
>for staging just before getting the eggs out of its' mouth, or whatever, if
>you wait it out? There are a number of approaches
>
>I am pursuing a 250 gallon ferrocement tank design that would work well as=
a
>Tilapia breeding tank for 3 females and 1 male, or even a bit more.
>
>Did you ever get that 5 gallon Tilapia egg hatching thing I sent out? It=
is
>really simple. Just an aquarium net set flat on top of a 5 gallon bucket
>with the net hanging down into the water, and the water flows gently into
>the mouth of the net. The eggs sit at the bottom of the aquarium net and
>gently tumble around, so they are
.what, 6 or 8 inches below the surface=
of
>the water in the bucket, and there is an exit hole or pipe in the side of
>the bucket at the appropriate control height, or depth, on the bucket, see?
>
>It's kinda like a cheap-o McDonald Jar
.not quite the same principle,=
but
>kinda.>Are you familiar with those? Where the eggs tumble down at the bottom of
>the McD jar from a slow, steady stream of clean, highly oxygenated water,
>then the fry, as they hatch out, are able to swim up a tube where they are
>collected via a collection stream that dumps them into a circular tank
.?
>It is kinda involved, and that's probably more elaborate than what you are
>looking for, but it is food for thought.
>
>Ted
F. Carl Uhland, DVM
Facult=E9 M=E9decine V=E9t=E9rinaire
University of Montreal
3200 rue Sicotte
Saint-Hyacinthe (Qu=E9bec) J2S 7C6
T=E9l: 450-773-8521; ext: 8317
Fax: 450-778-8116
Carl.F.Uhland 'at' umontreal.ca
| Message 2
Subject: Re: Aquaponics Digest - Sun 05/20/01-ORCHIDS
From: DAVEINBHAM 'at' aol.com
Date: Tue, 22 May 2001 12:33:34 EDT
In a message dated 5/20/01 11:08:10 PM Central Standard Time,
aquaponics-digest-request 'at' townsqr.com writes:
<< Cattleyas for instance need bright
direct sunlight >>
******************************************************************
I don't think so. Cattleyas like about 5,000 foot candles. Most places in
continental USA get about 10,000 to 11,000 on a clear day. More at high
altitudes. So, about 50% or more shade cloth between the Cattleyas and the
clear blue sky is needed to keep from burning the hell out of them.
There are more species of orchids than any other plant family, so you should
expect an exception to just about any rule of thumb on growing them. Vandas,
most Bulbophylums, and some Oncidiums can be grown in full sun if you do it
right. The secret is that if you live where it freezes in winter, do not
bring them out of the greenhous in spring until the night temperature exceeds
50 F
And a little partial shade is handy for a few days while they adjust to the
full sun, otherwise you will burn them.
I have not yet tried growing orchids aquaponically but I have grown them
hydroponically so there should be no problems if basic culture is followed.
Another good rule of thumb on orchids is that orchids with pseudobulbs (
Cattleya, Oncidium, Cymbidium etc.) generally like their roots to dry out a
bit between waterings. Orchids without pseudobulbs ( Vanda, Phaelonopsis,
Paphiopedilums etc ) generally go not need to dry out between waterings.
Hydrofarm has featured a Cattleya growing in one of thier systems in thier
ads for years. The secret is lots of air to the roots.
Most orchids in the tropics grow halfway up a tree halfway up a mountain.They
are fertilized by bird poop washing down from the treetops, so fish poop
should work equally well.
Regards,
Dave
| Message 3
Subject: 05/20/01-ORCHIDS
From: fishmanbruce 'at' webtv.net (Bruce Schreiber)
Date: Tue, 22 May 2001 12:02:12 -0500 (CDT)
--WebTV-Mail-19971-2375
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I stand corrected in Arizona I used to hang my Catts. from Mesquet trees
in the summer but in the winter when the sun was low in the sky they got
more direct light and seemed to do fine .
Bruce
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From: DAVEINBHAM 'at' aol.com
Message-ID:
Date: Tue, 22 May 2001 12:33:34 EDT
Subject: Re: Aquaponics Digest - Sun 05/20/01-ORCHIDS
To: aquaponics 'at' townsqr.com
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In a message dated 5/20/01 11:08:10 PM Central Standard Time,
aquaponics-digest-request 'at' townsqr.com writes:
<< Cattleyas for instance need bright
direct sunlight >>
******************************************************************
I don't think so. Cattleyas like about 5,000 foot candles. Most places in
continental USA get about 10,000 to 11,000 on a clear day. More at high
altitudes. So, about 50% or more shade cloth between the Cattleyas and the
clear blue sky is needed to keep from burning the hell out of them.
There are more species of orchids than any other plant family, so you should
expect an exception to just about any rule of thumb on growing them. Vandas,
most Bulbophylums, and some Oncidiums can be grown in full sun if you do it
right. The secret is that if you live where it freezes in winter, do not
bring them out of the greenhous in spring until the night temperature exceeds
50 F
And a little partial shade is handy for a few days while they adjust to the
full sun, otherwise you will burn them.
I have not yet tried growing orchids aquaponically but I have grown them
hydroponically so there should be no problems if basic culture is followed.
Another good rule of thumb on orchids is that orchids with pseudobulbs (
Cattleya, Oncidium, Cymbidium etc.) generally like their roots to dry out a
bit between waterings. Orchids without pseudobulbs ( Vanda, Phaelonopsis,
Paphiopedilums etc ) generally go not need to dry out between waterings.
Hydrofarm has featured a Cattleya growing in one of thier systems in thier
ads for years. The secret is lots of air to the roots.
Most orchids in the tropics grow halfway up a tree halfway up a mountain.They
are fertilized by bird poop washing down from the treetops, so fish poop
should work equally well.
Regards,
Dave
--WebTV-Mail-19971-2375--
| Message 4
Subject: Re: Aquaponics Digest - Sun 05/20/01-ORCHIDS
From: Peggy & Emmett
Date: Tue, 22 May 2001 13:34:12 -0400
At 12:33 PM 5/22/2001 EDT, DAVEINBHAM 'at' aol.com wrote:
>I have not yet tried growing orchids aquaponically but I have grown them
>hydroponically so there should be no problems if basic culture is followed.
>Another good rule of thumb on orchids is that orchids with pseudobulbs (
>Cattleya, Oncidium, Cymbidium etc.) generally like their roots to dry out a
>bit between waterings. >Dave
>
That's exactly what I suspected. The aquaponic system delivers good gas
exchange but it never drys out
.Emmett
| Message 5
Subject: Re: Fish Hatchery
From: fishmanbruce 'at' webtv.net (Bruce Schreiber)
Date: Tue, 22 May 2001 13:34:48 -0500 (CDT)
Guys Use the older enamelled metal refrigerator liners in banks
of six or so on stands so you get better use of space and cut out an end
leaving a 1/2 inch edge to silicone on a plate glass viewing window they
have worked for 40 years in some of my friends systems
Bruce
| Message 6
Subject: Re: Tilapia growth
From: fishmanbruce 'at' webtv.net (Bruce Schreiber)
Date: Tue, 22 May 2001 14:11:32 -0500 (CDT)
Steve I will try to get off on friday night So Sherry and I
should see you then .
If you want I will take the breeders I really will! But with my help
you wont have any problem growing out Tilapia fast from now on if you
decide to give them another try, Starting from scratch like you did with
Zero experience takes balls so I don't see you giving up that easy.
Its up to you or I could get them started for you when your ready.
Steve you would never beleive how many fish that I"ve killed over the
years.
You might recal hearing about the mass fish extinctions caused by a
meteator strike HELL NO THAT WAS ME
Bruce
| Message 7
Subject: Re: Marketing Tips?
From: dreadlox 'at' cwjamaica.com
Date: Tue, 22 May 2001 14:45:07 -0700
Examples.
http://www.aces.edu/department/extcomm/publications/anr/anr-962/anr-962.htm
http://www.aces.edu/department/extcomm/publications/anr/anrfish.html
Peace,
Mike,
JAMAICA
cmccarth 'at' wvu.edu wrote:
>
My question does anyone have any good sources of information on
marketing
> products or business start-up help that they would be willing to share?
>
| Message 8
Subject: email address change
From: "Virginia Gilmore"
Date: Tue, 22 May 2001 15:10:56 -0600
Please change the address for me From vagilmore 'at' surfbest.com to
wcfarm 'at' juno.com. Thank you.
| Message 9
Subject: RE: Tilapia growth
From: "Carlos Arano"
Date: Tue, 22 May 2001 07:30:20 -0300
Ted:
Is nice to know you are alive.
Best for you.
Carlos
----- Original Message -----
From: TGTX
To:
Sent: Monday, May 21, 2001 9:24 PM
Subject: Re: Tilapia growth
> > > I'm kind of bummed. Going to go. Best to All.
>
> Hey, Steve, I'll tell you what
man, as the bumpersticker
says
"Ca-Ca
> Occurs"
and Sometimes the Compost Hits the Fan
.>
> Just last night, I hardly slept
because of the Mondo storm we had.
> The lightning strikes were giving me bad flashbacks,
> man
.incoming!!
.incoming!!
>
.hit the deck!!
>
> The hail was driving into my windows
horizontally
at about 70 mph.
> Water was coming in under the threshold of the doors and through the
windows
> on one side of the house
and I have a fairly secure little brick
> house
on a hillside in the middle of the prairie
.no rivers can breach
> this far up hill
but
.Oy Veh!!
>
> When I got up this mornin', I found that the 36 tomato plants in my beauty
> little garden on the south side of the house were totally hammered
Some
> of the chickens were out of their normally snug, cozy, chicken tractor,
> complaining severly to me about their ordeal last night, and looking all
the
> world like drowned wharf rats
and
>
> My 12 foot diameter, 4 foot deep, conical bottom fiberglas fish tank shell
> that was waiting patiently for me to assemble and begin some serious fun
and
> games with
half of it was lifted up, and
get this
.torn in
half
we
> are talking 300 lbs of serious mass getting chewed up and spit out and
> thrown 30 yards from where it rested
I mean, serious fiberglas shell
> gettin' shorn asunder like wet cardboard, man.>
> I was bummed
.but you know what? I am so glad and grateful that I am
> alive
and the weird thing is, that not one petal of the roses on our
rose
> bush were shaken off on the west side of the house, and the cats
with 3
> new baby kittens were there waiting for me on the front porch this morning
> like this was all business as usual
"where's our treat?"
>
> My attached greenhouse made it all through this
.totally unscathed
.>
> And
we are all O.K
just really tired right now.
>
> So, stuff happens, and we just have to try to make the best of it if we
can.
>
> Blessings,
>
> Ted (Lightnin') Ground
> (Happy to be alive today.)
>
>
>
| Message 10
Subject: Israeli Innovations Slam Dunk It Again
From: "TGTX"
Date: Tue, 22 May 2001 18:47:38 -0500
Guys and gals, you gotta admire the ingenuity of Israeli innovations and
developments in practical controlled environment agriculture. Amen?
Check it out:
http://www.newscientist.com/dailynews/news.jsp?id=ns9999717
A smart sensor that gives crops only as much water as they need
dramatically increases yields
A smart irrigation sensor that gives plants only as much to drink as
they need can increase tomato yields by more than 40 per cent. The
sensor has been developed by Yehoshua Sharon and Ben-ami Bravdo at the
Hebrew University of Jerusalem's faculty of agriculture in Rehovot,
Israel.
The researchers say that their system not only increases the yield of
crops, but it also dramatically reduces water usage--by up to 60 per
cent for some crops.
At the heart of the system is an electronic sensor that clips onto a
plant leaf and measures its thickness to an accuracy of 1 micrometre.
"A leaf's thickness is dependent on the amount of water in a plant,"
says Sharon. "A healthy leaf is 60 per cent water." A thin leaf is a
sure sign that the plant is suffering stress because it is thirsty, and
stress is bad for yields.
Correct timing
The sensor consists of two plates, one fixed and the other
spring-loaded, which together grip the leaf. The moving plate is
connected to a small potentiometer that regulates the voltage in an
electrical circuit. As the leaf's thickness changes, the plate moves,
causing a change in the voltage. This signal is fed to a processor that
adjusts the plant's water supply.
Unlike conventional irrigation systems, which water crops periodically,
the Israeli system waters the plants continuously, but adjusts the flow
to the plants' needs. "The idea is to give the plant the proper amount
of water at the correct time, according to what the plant requires,"
says Sharon.
Field studies show the system increases the yields of several crops
while reducing consumption of water.
Yields of grapefruit increased by 15 per cent while needing 40 per cent
less water. For peppers the yield rose 5 per cent while water usage fell
by 60 per cent. Tomato plants yielded 40 per cent more fruit while
consuming 35 per cent less water.
Surprising savings
"It is an interesting idea," says John Sadler, a soil scientist at the
US government's Agricultural Research Service in Florence, South
Carolina. "Other researchers have measured stress by measuring a plant's
temperature or stem thickness. But I haven't heard of anyone doing
irrigation at such a refined level," he says.
But Sadler is a little surprised by the figures for water savings. "They
would depend on the technique you're comparing these results with," he
says. Sharon says the savings are based on comparisons with the Israeli
government's recommendations for irrigating crops.
He admits that the system has to be very reliable if it is to be
effective. "Because the plants are watered continuously they are more
susceptible to sudden changes in water supply," he says. "This means our
system has to operate very reliably."
The researchers have founded a company called LeafSen to sell the new
irrigation system, and they hope to start marketing it within the next
few months.
| Message 11
Subject: Oy Vey!!
From: "STEVE SPRING"
Date: Tue, 22 May 2001 21:18:23 -0500
Hey Ted,
Man, you always make me laugh!
I watched an old edition of "Matlock" today. He went back to his old home
town. People were all "hitting" on him because he was rich and famous. Moral
of story: He defended a kid an obviously got him off but at the end of the
story a guy gave him a $5 bill and told him to count his blessings.
I'm having all of these problems right now, you almost get blown off the
face of the earth, it never stops raining here
.(I have such a wonderful
wife. She always worrys about my problems.) I was going out the door tonight
to see about my tomatos and remaining Tilapia and just stopped "mid stride".
She asked me what the problem was
(I thought about Matlock and the $5
bill
.looked at her and said, "I'm just counting my blessings.")
This has nothing to do with aquaponics and I will try to not philosophize
(sp) anymore.
Steve
----- Original Message -----
From: "TGTX"
To:
Sent: Monday, May 21, 2001 7:24 PM
Subject: Re: Tilapia growth
> > I'm kind of bummed. Going to go. Best to All.
Hey, Steve, I'll tell you what
man, as the bumpersticker says
"Ca-Ca
Occurs"
and Sometimes the Compost Hits the Fan
.
Just last night, I hardly slept
because of the Mondo storm we had.
The lightning strikes were giving me bad flashbacks,
man
.incoming!!
.incoming!!
.hit the deck!!
The hail was driving into my windows
horizontally
at about 70 mph.
Water was coming in under the threshold of the doors and through the windows
on one side of the house
and I have a fairly secure little brick
house
on a hillside in the middle of the prairie
.no rivers can breach
this far up hill
but
.Oy Veh!!
When I got up this mornin', I found that the 36 tomato plants in my beauty
little garden on the south side of the house were totally hammered
Some
of the chickens were out of their normally snug, cozy, chicken tractor,
complaining severly to me about their ordeal last night, and looking all the
world like drowned wharf rats
and
My 12 foot diameter, 4 foot deep, conical bottom fiberglas fish tank shell
that was waiting patiently for me to assemble and begin some serious fun and
games with
half of it was lifted up, and
get this
.torn in half
we
are talking 300 lbs of serious mass getting chewed up and spit out and
thrown 30 yards from where it rested
I mean, serious fiberglas shell
gettin' shorn asunder like wet cardboard, man.
I was bummed
.but you know what? I am so glad and grateful that I am
alive
and the weird thing is, that not one petal of the roses on our rose
bush were shaken off on the west side of the house, and the cats
with 3
new baby kittens were there waiting for me on the front porch this morning
like this was all business as usual
"where's our treat?"
My attached greenhouse made it all through this
.totally unscathed
.
And
we are all O.K
just really tired right now.
So, stuff happens, and we just have to try to make the best of it if we can.
Blessings,
Ted (Lightnin') Ground
(Happy to be alive today.)
| Message 12
Subject: "Giving Up!"
From: "STEVE SPRING"
Date: Tue, 22 May 2001 22:09:13 -0500
Hi Bruce,
Didn't want to burden Paula's list anymore with this, but I wanted to clear
up a couple of things. "Giving up" is not in my vocabulary. I have no desire
to give up. I just want to change directions
My relationship with Tilapia has been very labor intensive, very costly and
non-rewarding. I have no desire to give up on my aquaponics venture, I just
want to go into something different. Hey, I love these little
"lemon-yellows". My wife loves her little "fat fish". I just loved my
initial Tilapia breeders. I nicknamed them the "Chihuahuas". (They were Mike
Sipe's "Chocolates") They would just wiggle like crazy whenever they saw me.
Come to the surface and eat right out of my hand. BUT, THEY ARE DEAD! (Makes
me sad to think about them.)
I was told when I initially started this business that Tilapia could be
grown at a rate of 1/2 lb Tilapia per gal of water and that was what I was
trying to attain. This is probably attainable if you have a TREMENDOUS
filtration system and a pure O2 input. My 5 growbeds were obviously
inadequate to handle this quantity of fish. I know that I have blasted Mike
Sipe's fish in the past. This is personal. Has nothing to do with his fish.
The original breeders that I got from him were absolutely phenomenal and
produced, obviously, maximum quantities of offspring.
I believe, in hindsight, that this was ultimately the problem. I just had
too many fish for my system to handle. The offspring started breeding and
then it was a catastrophic endless cycle of problems.
After my loss of several hundred fish, I now have +/- 100 fish in my 800 gal
tank and the water clarity is unbelievable. You can see the "theoretical"
dime at the bottom of the tank.
I'm really posting this message to the "newbies" on the list. Beware of
exaggerated claims. What do they say, "If it sounds too good to be true, it
probably is."?
I believe if I had stuck to maybe 1/4 lb fish/gal of water, I would have
been o.k. But, what do you do when you have hundreds of babies a week
.do
you just kill them?
Just food for thought.
Steve
| Message 13
Subject: Re: Oy Vey!!
From: marc 'at' aculink.net
Date: Tue, 22 May 2001 21:36:20 -0600
>
> This has nothing to do with aquaponics and I will try to not philosophize
> (sp) anymore.
Well maybe it does.
There are several learning styles and ways of operating in
this world with various degrees of risk involved with those
styles.
In the world of Aquaponics it seems to me that the tried and
true path works in almost a boringly easy fashion. The worst
thing I've heard about the S&S system is that it is only
partially tornado proof.
As folks swerve/depart/turn away/go bye-bye from the tried
and true I guess it satisfies the
inventor/hunter-gatherer/male bonding need or something else
well documented and debated by NOW (ain't us guys so
fascinating!) but the risk increases until fish die in great
quantities, PETA complains and life is exciting again.
Seriously though, the emergency water you added reminded me
that maybe it would be a good thing to have suitable water
on hand for emergency fish water.
Perhaps separating the breeders at a certain point is
another lesson.
> I don't have a clue as to what these fish are.
Sorry. Should have given you the links for the fish I
recommended Here goes:
http://google.yahoo.com/bin/query?p=Clarias+batrachus&hc=0&hs=0
http://google.yahoo.com/bin/query?p=Anabas+testudineus&hc=0&hs=0
Enjoy!
Marc
| Message 14
Subject: Re: Working with Fiberglass
From: "David Atkinson"
Date: Tue, 22 May 2001 23:54:53 -0400
Hi,
Does anyone on this list have any information about working with Fiberglass?
I want to build some tanks using Fiberglass, but need information about how
to work with Fiberglass for a do-it-yourselfer.
i.e. using resins, the Fiberglass matting etc.
Any websites, or offline source would be appreciated.
Thanks All.
David A
(from JAMAICA W.I.)
atkindw 'at' cybervale.com
----- Original Message -----
From: TGTX
To:
Sent: Tuesday, May 22, 2001 7:47 PM
Subject: Israeli Innovations Slam Dunk It Again
> Guys and gals, you gotta admire the ingenuity of Israeli innovations and
> developments in practical controlled environment agriculture. Amen?
> Check it out:
>
> http://www.newscientist.com/dailynews/news.jsp?id=ns9999717
>
> A smart sensor that gives crops only as much water as they need
> dramatically increases yields
>
> A smart irrigation sensor that gives plants only as much to drink as
> they need can increase tomato yields by more than 40 per cent. The
> sensor has been developed by Yehoshua Sharon and Ben-ami Bravdo at the
> Hebrew University of Jerusalem's faculty of agriculture in Rehovot,
> Israel.
>
> The researchers say that their system not only increases the yield of
> crops, but it also dramatically reduces water usage--by up to 60 per
> cent for some crops.
>
> At the heart of the system is an electronic sensor that clips onto a
> plant leaf and measures its thickness to an accuracy of 1 micrometre.
>
> "A leaf's thickness is dependent on the amount of water in a plant,"
> says Sharon. "A healthy leaf is 60 per cent water." A thin leaf is a
> sure sign that the plant is suffering stress because it is thirsty, and
> stress is bad for yields.
>
> Correct timing
>
> The sensor consists of two plates, one fixed and the other
> spring-loaded, which together grip the leaf. The moving plate is
> connected to a small potentiometer that regulates the voltage in an
> electrical circuit. As the leaf's thickness changes, the plate moves,
> causing a change in the voltage. This signal is fed to a processor that
> adjusts the plant's water supply.
>
> Unlike conventional irrigation systems, which water crops periodically,
> the Israeli system waters the plants continuously, but adjusts the flow
> to the plants' needs. "The idea is to give the plant the proper amount
> of water at the correct time, according to what the plant requires,"
> says Sharon.
>
> Field studies show the system increases the yields of several crops
> while reducing consumption of water.
>
> Yields of grapefruit increased by 15 per cent while needing 40 per cent
> less water. For peppers the yield rose 5 per cent while water usage fell
> by 60 per cent. Tomato plants yielded 40 per cent more fruit while
> consuming 35 per cent less water.
>
> Surprising savings
>
> "It is an interesting idea," says John Sadler, a soil scientist at the
> US government's Agricultural Research Service in Florence, South
> Carolina. "Other researchers have measured stress by measuring a plant's
> temperature or stem thickness. But I haven't heard of anyone doing
> irrigation at such a refined level," he says.
>
> But Sadler is a little surprised by the figures for water savings. "They
> would depend on the technique you're comparing these results with," he
> says. Sharon says the savings are based on comparisons with the Israeli
> government's recommendations for irrigating crops.
>
> He admits that the system has to be very reliable if it is to be
> effective. "Because the plants are watered continuously they are more
> susceptible to sudden changes in water supply," he says. "This means our
> system has to operate very reliably."
>
> The researchers have founded a company called LeafSen to sell the new
> irrigation system, and they hope to start marketing it within the next
> few months.
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