Aquaponics In Developing Countries

44 Pages·2005·2.32 MB·English

by  Rebecca Nelson

Issue # 38 ® Aquaponics J o Iusrsnuael # w38w w . a q u a p o n i c s j o u r n a l . c o m 3 r3drd Q Quuaratreterr, ,2 2000055

$10 USD
Aquaponics for
Developing Countries
Eels and
Citrus!

1
Antarctic
Hydroponics

Aquaponics Lesson Plan
Hydroponics in Germany
SIFT Aquaponics
Editor’s Note
Industry News
Q and A by Dr. James Rakocy
New Products - To Help You Learn and Grow
Happenings - Conferences, Trade Shows, Workshops
Resource List - The Who, What and Where of the Industry
As I See It...by Geoff Wilson
Aquaponics is the combination of aquaculture (fish farming)
and hydroponics (growing plants without soil).
Issue # 38 Aquaponics Journal www.aquaponicsjournal.com 3rd Quarter, 2005

The Aquaponics Journal is
Editor’s Note:
published quarterly by

Nelson/Pade Multimedia
What an issue! The articles within crisscross the globe
Mariposa, CA, USA
from the US to Australia, Germany to Antarctica. Our con-
copyright 2005
tributing authors make this a great publication, with inno-
all rights reserved
vative ideas about aquaponics and coverage of the develop-
ments in our industry from around the world. Publishing
Electronic Subscription:
this journal gets more fun and interesting with each issue as
the installations of aquaponic systems increase, technology • $29/year
continues to develop, outside recognition expands and in- Printed Subscription:
terest grows exponentially. • $39/year - within the US
• $49/year - Canada and Mexico
The launch of the Aquaponics Association of Australia is a • $69/year - International
monumental step in networking individuals with an interest includes First Class or Air Mail postage
in aquaponics and sharing information about aquaponics.
You can learn more about this budding organization in For subscription or advertising
“Industry News.” information, please contact:
Nelson/Pade Multimedia
The Annual Tilapia and Aquaponics short course at the PO Box 1848,
University of the Virgin Islands took place in June and was Mariposa, CA 95338, USA
2 booked full with 33 students, as usual. Next year, in an ef- ph 209-742-6869
fort to accommodate more people who want to attend, Dr. Fax: [phone]
Rakocy and the UVI research scientists will be offering e-mail: [email protected]
their course twice. Stay tuned for dates and details. www.aquaponicsjournal.com
www.aquaponics.com
Other aquaponics courses are taking place as well. Aqua-
culture International, Andrews, North Carolina Editor, Co-Publisher:
(www.aquacultureinternational.org ) and Morningstar
• Rebecca L. Nelson
Fisherman, Dade City, Florida,

(www.morningstarfisherman.org) are both offering special-
Co-Publisher
ized courses in aquaponics.
• John S. Pade

Quickly approaching is the International Conference and
Contributing Authors:
Exhibition on Soilless Culture in Singapore. This confer-
• Travis Hughley
ence takes place September 5-8, 2005 and will host a num-
• Rebecca L. Nelson
ber of speakers addressing aquaponics as well as organic
• Lane Patterson
culture, hydroponics and related topics. This conference
will be a hub of activity relating to aquaponics with indus- • Dr. James Rakocy
try experts presenting research and information. For more • C.P. Gloria Samperio Ruiz
information and to sign up, visit the conference website at • Geoff Wilson
www.icesc-2005.com. We will be reporting on the presen-
tations, research and conference content in the next issue. Logo Design: Danilo Piccioni

Until next time, Creative Consultant: Kita B.
Rebecca
Issue # 38 Aquaponics Journal www.aquaponicsjournal.com 3rd Quarter, 2005
In This Issue
Features:

12 Antarctic Hydroponics
Lane Patterson, operator of the hydroponic vegetable growth unit at McMurdo
Station, Ross Island, Antarctica, provides insight into life in Antarctica and growing
fresh vegetables for the residents of the research stations at Ross Island and the
South Pole.

16 Aquaponics for Developing Countries

Travis Hughley shares information on the aquaponic system he has designed for use

in developing countries. His “aquaponic float valve” is the key to it’s success.

19 Eel and citrus Culture Combined in Australia

Geoff Wilson contributes this article which informs us about a unique cooperative
effort between an eel farmer and a citrus grower.

22 Advancements in Hydroponics in Germany
3

C.P. Gloria Samperio Ruiz shares her experiences from a recent trip to Germany where
she had the opportunity to get a first-hand look at the advancements in hydroponic
technology at University of Dresden-Pillinitz and the Institute of Vegetables and Or
namental Crops, Grossbeeren.

26 SIFTS Aquaponics Research Awarded A$1.4 Million

In an update from Geoff Wilson, we learn the ongoing aquaponic research into the
Western Australian semi-intensive floating tank system (SIFTS) now has a three-year
budget from July 2005 of A$1.4 million (about US$1.1 million).

28 Aquaponics Lesson Plan, # 6: Introduction to Botany

Rebecca L. Nelson contributes the sixth in a ten-part series of aquaponic lesson plans.

Departments:
On the cover:
2 Editor’s Note
Travis Hughley shows one of
4 Industry News
the tilapia he has grown in
8 Q and A by Dr. James Rakocy
33 Resource List his aquaponics system de-
38 Happenings signed for use in developing
40 Back Issues List
countries. See related story
42 As I See It by Geoff Wilson
on page: 16
Issue # 38 Aquaponics Journal www.aquaponicsjournal.com 3rd Quarter, 2005
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Mainstream Aquaculture Plans
World’s Largest Aquaponics Project
Contributed by Geoff Wilson
Melbourne, Australia—The world’s largest aquapon-
ics investment is likely to be developed from an urban
aquaculture project by Mainstream Aquaculture Pty
Ltd., at Werribee, a satellite city of Melbourne, Austra-
lia. It is also likely to become the world’s largest urban
agriculture investment if five-year plans come to frui-
tion, with an annual production of 200 tons of fish and
up to 1,400 tons of fruit and vegetables from the fish
wastes.
This is the first Mainstream Aquaculture RAS shed in the in-

dustrial park at Werribee, Victoria. It is currently producing
The project is already producing 50 tons of fin fish a
50 tons of live fish per year for the nearby Melbourne mar-
year in a large building atop a warm-water aquifer be-
ket. The small shed in the foreground is where the bore goes
ing used to grow the tropical barramundi and the inland
down to the geothermal aquifer - which makes it possible for
Murray Cod for the Melbourne live fish market. Dr.
4 the tropical barramundi and the sub-tropical Murray Cod to
Paul Harrison is manager of the project, which has used be grown in a cold, temperate climate.
the consultancy services of Australia’s pioneer aquaponics
operation, Taylor Made Fish Farms Pty Ltd. at Newcastle,
New South Wales, about 1,100 kilometres north of Werribee.
.
The heated water from the aquifer is pumped from a simple bore at
around 28o Celsius to keep the 10,000-liter round fish tank modules at a
constant 27o - 28o all day. Four people are employed in the current op-
eration—three managing the fish and one maintaining equipment. The
investment shift to scaled up aquaponics will come as the company
buys, constructs and equips another three large buildings.

One of the key people behind this existing aquaculture and planned aq-
uaponics development is Professor Rocky de Nys, a leader in Australian
aquaculture in both his academic work as energetic head of the Depart-
ment of Aquaculture, School of Marine Biology, James Cook Univer-
sity, at Townsville and, now, as a world-class leader in commercial aq-
uaponics. Professor de Nys was a major shareholder and director of Dr. Harrison inspects one of the important
Taylor Made Fish Farms Pty Ltd., near Newcastle, which pioneered items of technology Mainstream Aquaculture
Australian aquaponics by producing 600 kg of barramundi a week and Pty Ltd bought from Australia's pioneering aq-
20,000 heads of lettuce a month from the barramundi wastes. For every uaponics company, Taylor Made Fish Farms
ton of fish waste, about seven tons of vegetables can be produced. Pro- Pty Ltd. It is the patented solids separator that
fessor de Nys has resigned his directorship in Taylor Made (but not his will be important for the planned expansion of
Mainstream into aquaponics. Currently fish
shareholding) in favor of a directorship in Mainstream Aquaculture.
wastes go into the domestic sewer system at a

substantial cost.
At James Cook University Professor de Nys is now supervising studies
of the various strains of golden perch, an Australian native fish that has great promise as an aquaculture fish well
suited to aquaponics and to recirculating aquaculture systems based on geothermal aquifers in cold climates.
Issue # 38 Aquaponics Journal www.aquaponicsjournal.com 3rd Quarter, 2005
IIInnnddduuussstttrrryyy NNNeeewwwsss
C-Box” now in polypropylene
Contributed by Geoff Wilson
Queensland, Australia—The Cumminscrop Limited “C-
Box” fish-farm-in-a-container is now being made in food-
grade polypropylene. The first fish farm is being set up at
Yatala, between Brisbane and the Gold Coast in sub-tropical
Australia., using seven of these outdoor containers. Housing a
ton of fish in 6,000 liters of water (fresh or salt). Results from
the Yatala commercial development are being eagerly awaited
by many people interested in both aquaculture and aquaponics
using Cumminscorp technology. The original concept of the
"C-Box" was for the fish wastes to be used in an organic hy-
droponic unit. This has yet to be developed, but is intended to
be part of the Cumminscorp range of water conditioning prod-
ucts. If the aquaponic system works for the "C-Box," it is ex-
pected to be a key item of equipment for urban aquaponics in
configurations that have the aquaculture at ground level or in a 5
basement and the fish wastes piped to a rooftop for organic
hydroponics.
RRaakkooccyy
&& AAssssoocciiaatteess
A network of consultants for:
Aquaponics
Aquaculture

Hydroponics

For information on

our range of services,
contact D. James Rakocy
at 340-773-6176 or [email protected]
Issue # 38 Aquaponics Journal www.aquaponicsjournal.com 3rd Quarter, 2005

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International Students Graduate
Program with Experience in Aquaponics!
Dade City, Florida—On May 5,
2005, Morning Star Fisherman
awarded certificates of completion to
17 CASS (Cooperative Association of
Student Scholarship) students from
Guatemala, Honduras, Nicaragua and
El Salvador. These students have
been studying at Hillsborough Com-
munity College on a two year pro-
gram and will be returning to their
homelands in July to begin two years
community service, teaching others
the art and science of aquaculture and
aquaponics. Graduating students
were: Maria Perez, Ana Cutillo,
Goldin Mechor, Carlorafael Aceituno,
6
Victor de la Cruz, Nelson Galvez, Marcia Mayorga, Sandra Aguilar, Yolanda Giron, Glenys Carmona, Aliben Paz,
Edwin Alvarez, Katty Mothen, Ivania Ruiz, Juan Nunez, Ismael Torrez, and Domingo Rayo. For more information
on Morning Star Fishermen and the programs they offer, visit www.morningstarfisherman.org.
New Courses Offered by Aquaculture International
Barrel Aquaponics Producing Fuels from Ag Wastes
Do you want to get started producing a constant supply fish and Are you interested in economically converting agricultural
vegetables in an efficient, inexpensive small-scale system? If wastes into valuable fuels and efficiently utilizing the by-
so, you will want to attend a practical workshop entitled, products? If you are, plan to attend the Producing Fuels from
“Barrel Aquaponics – Construction and Operation” held at Agricultural Wastes Course held at Camp Living Water, Bry-
Camp Living Water, Bryson City, NC, October 10 & 11, 2005. son City, NC, September 27 – 30, 2005. Instruction will focus
Instruction will focus on “Aquaponics,” which is the combining on the production of methane from animal and plant waste,
of aquaculture and hydroponics for mutual benefit. Lecture and but other fuels will be covered such as ethanol and bio-diesel.
AV presentations will include barrel system construction, se- Construction of various types of digesters from locally avail-
lecting fish and plants to produce, management practices, main- able material and discarded products, day-to-day operation,
taining water quality, system balance, day-by-day operation and utilizing the fuel for heating, running generators and other
considerations for expansion plans which are adaptable to all engines, the profitable use of the valuable by-products and
types of environments. alternative complimentary power production will all be cov-
ered during the course.
On Tuesday, each attendee will be given an opportunity to con-
struct a highly productive, small-scale system (from barrels), This will prove to be a valuable and timely course for farm-
capable of producing fish and a large variety of vegetables, ers, agriculture teachers, interested individuals and those who
greens & herbs. This can be used as a learning tool at home, want to use as a “helps ministry” outreach.
school, on the farm or as an effective ministry outreach project
before expanding to a larger operation.
Come and enjoy the beauty of the Great Smoky Mountains and enjoy fellowship with others of like interest.
For more information or to register, visit: www.aquacultureinternational.org
or write: Aquaculture International, Inc., PO Box 606, Andrews, NC 28901.
Issue # 38 Aquaponics Journal www.aquaponicsjournal.com 3rd Quarter, 2005
IIInnnddduuussstttrrryyy NNNeeewwwsss
AAA to launch in November
Restoring Coastal Ponds in
The Aquaponics Association Australia will be launched
Aceh Province, Indonesia
in November, 2005. Geoff Wilson, convener of the
AAA said that it’s members would be anyone interested YELLOW SPRINGS, Ohio – YSI Incorporated has donated over
$75,000 (USD) to help Indonesian fish farmers recover from the
in the technology of aquaponics – which started with the
long-term effects of the 2004 Indian Ocean tsunami. YSI’s “Fund
famed Hanging Gardens of Babylon 2,500 years ago, but
for Rebuilding Aquaculture in Tsunami-Affected Areas” has raised
is rapidly advancing with technology innovations devel-
more than $25,000 in private donations from its employees, direc-
oped in the United States, Canada and Australia.
tors, retired employees and suppliers. In addition to this amount,

YSI’s non-profit Foundation has donated $50,000.
The principal focus will be hobbyist and home food pro-
duction systems and educational units operated by All of the funding is earmarked for projects in Indonesia which
schools. “Aquaponics is based on raising fish and using help fish farmers recover their tambaks (coastal ponds), tertiary
the fish wastes to grow food plants and flowers in or- water supply and equipment destroyed by the earthquake and
ganic hydroponic structures,” Mr. Wilson said. flooding. Most fish and shrimp farmers had small-scale operations
that directly supported their ability to earn a living. Aquaculture

without Frontiers, a non-profit organization, reports that over
Each month AAA breakfast meetings will:
50,000 people in Aceh Province, Indonesia, depended directly on
• Hear expert speakers on a subject related to
aquaculture for employment.
aquaponics.
• Enjoy a Slow Food breakfast that will incorporate YSI’s response to the tsunami 7
tastings of various fish and plant foods grown demonstrates that it is serious
aquaponically. about its mission to protect
life and natural resources. The
• Network with fellow aquaponic growers and
employees of the Company
appropriate experts in aquaponics, aquaculture and
felt strongly that they should
hydroponics.
help small business owners
• Make visits to aquaponic operations next to private affected by the disaster and
Mickey Sampson of RDIC (in yellow
homes, in schools or in commercial investments. immediately took action in shirt) using YSI equipment. He is work-
January to raise funds. ing with local people to test wells in
• Provide technical and regulatory information.
Banda Aceh following the tsunami.
Tim Grooms, Water Quality

Product Manager for YSI Environmental, states, “Our donations
“Both hobby and educational aquaponics are developing
are helping the people who are trying to rebuild their lives and
strongly in the United States,” Mr. Wilson said. “The
businesses. We felt that the best way to respond was to offer aid in
AAA will help bring this backyard hobby enjoyment and the specific area of aquaculture rather than making donations to a
educational opportunity more widely to Australia.” general aid organization. Aquaculture is an important market for
YSI and we wanted to give something back to this community.”
Wilson said the success of aquaponics was predicated on
the fact that one kilogram of fish waste could produce up Additionally, Endeco/YSI provided YSI’s EC300 water quality
meters to a nongovernmental organization – Resource Develop-
to seven kilograms of organically-grown vegetables. A
ment International-Cambodia (RDIC). These meters were used in
hobby or educational grower could grow at least 25 kilo-
Banda Aceh, one of the most damaged regions of Indonesia, to
grams of fish in a cubic meter of water a year in simple,
measure salinity in drinking water wells. Many wells were con-
low cost tank systems (compared with 55 to 70 kg/cubic
taminated during the tsunami and maintaining a clean water supply
meter of water in intensive commercial recirculation
is one critical component of the recovery process.
aquaculture systems).
YSI -- an employee-owned company in the United States -- is a leading
Further information: Geoff Wilson, Convener, Aq- provider of technology solutions and services for data collection and analy-
sis. The Company’s largest business unit, YSI Environmental, and its sub-
uaponics Association Australia, PO Box 5151, Mt Gra-
sidiary Endeco/YSI, provide instrumentation and monitoring systems to
vatt East 4122, Queensland, Australia. Phone +61 (0)7
global water quality and aquaculture markets. Please visit YSI’s web site,
3411 4524. Email: [email protected] www.ysi.com/environmental to learn more about the Company or contact
your local YSI dealer.
Issue # 38 Aquaponics Journal www.aquaponicsjournal.com 3rd Quarter, 2005
Q
Q
and
A
A
By
Dr. James Rakocy

Dr. James Rakocy, who answers ques-
tions concerning aquaponics in this
column, is the Director of the Univer-
sity of the Virgin Islands Agricultural
Experiment Station and has been doing
research in aquaponics for over 20
years. If you have a question for Dr.
Rakocy, please e-mail us at
[email protected].
8
Question Answer
G'day, Dear Andrew,
My name is Andrew Langelaan and I am studying Barramundi and Murray cod have been grown suc-
for the Advanced Diploma of Horticulture Produc- cessfully in aquaponic systems. I am not familiar with
tion at the University of Melbourne in Australia. silver perch, but I heard this fish mentioned as a pos-
After discovering aquaponics while doing an as- sible candidate for aquaponics. I suggest starting
signment last year, I have become very interested in with barramundi as there is interest in culturing this
doing a trial. I have several mini NFT systems on species in temperate regions in heated closed recircu-
hand that grow 18 plants and a 60L reservoir to go lating systems.
with each of them. I am planning on growing lettuce
in these kits. I have sourced out some fish from a The design ratio is based on the daily feed input per
local pet shop (barramundi, silver perch and unit of plant growing area. In raft hydroponics the
Murray cod) and was wondering if you could help design ratio varies from 60 to 100 g of fish feed per
me out with a few questions that I have. m2 of plant growing area per day. In an aquaponic
• Which of these species do you think would be system using nutrient film technique (NFT), there is
best for an initial trial? approximately 50% less water if all the other compo-
• How many fish (1 - 2 inches in size) will be nec- nents remain the same size. Therefore, the design ra-
essary in the systems I have? tio should be approximately 30-50 g/m2/day. I would
• What pH is preferable for the fish? use the lower ratio because there is less surface area
in an NFT system for biofiltration. I know from re-
• What is the best type of fish feed to produce the
search at UVI that optimum leaf lettuce density is16
best type of effluent?
plants/m2, which is roughly equivalent to the number
Any help you could give me would be greatly appre-
of plants that your system can grow. However, the
ciated.
surface area of your NFT troughs is probably lower.
Thanking you for your time,
You should measure it. It will be a faction of 1 m2.
Andrew F. Langelaan
Issue # 38 Aquaponics Journal www.aquaponicsjournal.com 3rd Quarter, 2005
Multiply this fraction by 30 g. The product will be the average daily Question
fish feeding rate. To illustrate, I will assume the plant growing area in
Aloha,
your system is 0.5 m2. You should therefore stock the rearing tank with
I am able to routinely grow
enough fingerlings to consume 15 g of feed per day.
beautiful Manoa lettuce in my

aquaponics system in Ha-
The fish stocking rate should result in final harvest density is 60 kg/m3
waii. My family (actually my
(0.5 lbs/gallon). This is equivalent to 3.6 kg (7.9 lbs) in your rearing
77 year old mother) loves aru-
tank, which is 0.06 m3 (15.8 gallons). If you raised the fish to a final
gula. I have tried on several
size of 500 g (1.1 lbs), you would stock about seven fish. Assume that
occasions to grow the tasty
the total weight of the seven fingerlings, 1-2 inches in length, is negligi-
leaves with little success. I
ble and that the total weigh gain of all the fish is 3.6 kg. Assuming that
have seen by searching the
the feed conversion ratio is 1.7 (1.7 lbs of feed produces 1 lb of fish
internet that arugula has a
gain), total feed consumption over a 6-month (180 days) growing period
copper requirement. Please
would be 6.1 kg or 6,100 g. Dividing total feed consumption by 180
inform me of your knowledge
days equals an average of 34 g of feed per day.
and experience of arugula. My

system is stocked with Chinese
Tackling this problem from both the plant and fish perspectives shows
catfish and has an adequate
that the average daily feeding rate should be in the range of 15-34 g.
supply of nitrate. Being a
With one small fish rearing tank, I suggest you use batch culture, which
closed system, the pH can get
means that all the fish would be stocked at one time and cultured for 180
down in the 6’s. Perhaps aru-
days. Feed input to the system will increase over time. Therefore, in the
gula needs a higher pH?
beginning there may be insufficient nutrients for good plant growth
Thank you,
while at the end there may be excess nutrients, which could be toxic to
Kathleen
the plants. One month is required after stocking for establishment of 9

bacteria in the biofilter (tank surface areas including NFT troughs).
Answer
During this period the fish must be underfed (do not feed them as much
Dear Kathleen,
as they want to eat), and there will not be enough nutrient accumulation
In the UVI raft system we have
for plant growth. Plants can be added at the beginning of the second
experienced high mortality of
month. In the latter part of the trial, nutrient levels may become too
arugula during the transplant-
high (exceeding 2,000 ppm as total dissolved solids). A small meter can
ing phase. It is a delicate plant
be purchased which easily measures TDS. Good plant growth generally
that cannot tolerate transplant-
occurs in the range of 200-2,000 ppm. If TDS exceeds 2,000 ppm, it
ing shock. However, if it can
can be decreased by exchanging some of the culture water with new wa-
survive transplanting, it grows
ter. You should install a glass wool filter to remove suspended solids
well. I suggest you experiment
from the stream of water that you pump to the NFT troughs.
with different seedling media

and transplanting techniques. I
pH should be maintained in the range of 7.0-7.5 by alternately adding
recommend using a mixture of
calcium hydroxide and potassium hydroxide. Small amounts should be
coconut fiber and vermiculate
added on a regular (almost daily) basis. Chelated iron should be added
as media and being extremely
once every 3 weeks at a concentration of 2 ppm. Use a complete diet
careful in not breaking any
(containing all required minerals and vitamins) of floating pellets with a
roots during transplanting.
minimum of 32% protein. The species you select may require higher
Arugula grows well in a pH
protein levels. Ask your local aquaculture extension agent for help in
range of 6.0 to 7.0. I suggest
selecting the best available feed. I recommend feeding ad libitum (as
keeping the pH near 7.0 to pro-
much as they can consume to 30 minutes) two to three times daily.
mote good nitrification, re-

moval of ammonia and nitrite
I have made many assumptions. The figures I have given you are in the
by bacteria.
ballpark, but you will have to do some trial and error work to optimize

your system.
Issue # 38 Aquaponics Journal www.aquaponicsjournal.com 3rd Quarter, 2005
Question Question
My class and I are working on an aquaponics I am considering using Schedule 20 3" pipe to con-
project. We have a 1,000 gallon fish tank which struct an NFT aquaponic system. I am a rookie and
we intend to raise tilapia in. Our assignment is wondering if the root structure will have problems
to find a way to do this without polluting our supporting the plants. I'd like to grow lettuce,
environment, so we decided to raise basil in an herbs, flowers and possibly tomatoes. How deep
aquaponics environment. Our problem is this: should I keep the water in the pipes?
We may use the floating Styrofoam sheet Thank you for your help!
method, but how exactly would we go about get- Josh Clark
ting the nutrients from the fish water up to the
roots of the plant? We have heard of the wick Dear Josh,
system, but could you please explain this a bit to I suggest you buy NFT troughs, which are designed
us and help us out? Any assistance you can give specifically for hydroponic plant production. The
would be greatly appreciated. trough bottoms are flat, which allows the roots to
Thank you spread out. There is also a small recess in the bot-
Samantha Morrison tom that gives additional space to the roots. The
troughs are angled so that water flows quickly and
Answer evenly through them as a film less than 1/8 inch
Dear Samantha, deep. The water distributes nutrients to all the roots
You should use sheets of closed cell polystyrene and provides oxygen. Removable plastic covers fit
that float on the water surface of the hydroponic over the troughs. There are openings in the covers
tank. Paint the surface of the sheets with a pota- for the plants to grow through, but the remainder of
ble grade of white latex paint. This protects the the trough is covered to prevent algal growth. The
10
polystyrene from sunlight, which would other- covers can be removed to easily clean the troughs in
wise quickly deteriorate it. Drill 2-inch holes in preparation for the next production cycle.
the sheets. For basil we have used a spacing of
8 inches between plants in rows and 12 inches PVC pipes on the other hand are less than desirable.
between rows. Use 2-inch net pots to support They are heavier and harder to work with. Plant
your transplanted seedlings. The net pots are 2 roots cannot spread out and therefore accumulate in
inches across at the top and 2 inches deep. masses that can become thick enough to block the
There is a lip at the top that rests on the polysty- water flow, which creates anaerobic conditions and
rene and prevents the net pot from falling root death. PVC pipes are more difficult to clean.
through. The net pot extend ½ inch into the wa-
ter. When the transplant is placed into the net It is my philosophy to always invest a little more at
pot it touches water, which moves upward the beginning of a project which makes a recurring
through capillary attraction, keeping the potting operation, such as pipe cleaning, simpler and faster.
media moist. Very quickly the plant roots grow In the long run you will save money and get better
through the webbing in the net pot and extend results.
deep into the water.

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