1. INTRODUCTION TO AQUAPONICS
How to Grow Food in Small Urban Spaces
Graham Wood

2. 1 WHAT IS AQUAPONICS?
Aquaponic food
production combines
soil-less vegetable
growing (Hydroponics)
and fish farming
(Aquaculture) within a
closed recirculating
system.
Aquaponic systems
mimic the natural
waterway ecosystems
and comprises a highly
effective growing
method for indoor food
production.

3. ISSUES WITH TRADITIONAL FOOD GROWING
 Dwindling fish stocks.
 Oil based fertilisers.
 Genetically modified.
 Soil depletion.
 Water shortage.
 Deforestation.
 Food miles.
 Climate change.

4. 2 PLANTS
Majority of vegetables can grow
in Aquaponics.
A variety of crops can be grown
-- Lettuce, Spinach, Chard,
Cucumbers, Kale, Spinach,
Rocket, Watercress, Basil,
Peppers, Tomatoes, and
Strawberries.
When starting a new system it is
better to grow a variety of salad
crops until your system is more
mature.
In Australia they have even
grown fruit trees.

5. 3 FISH
Factors that contribute to healthy fish are:
 Temperature
 Water quality (pH & Ammonia)
 Food.
Fish are fed, they digest and break down
the food producing waste by excreting
ammonia through urine, faeces, and gills.
Usually recommend using Gold fish or
Carp if starting off in Aquaponics as they
are the most robust fish and produce large
quantities of ammonia which is ideal for
Aquaponics.

6. 4 NITROGEN CYCLE
The Nitrogen cycle is the most significant
process within Aquaponics as it is responsible
for the conversion of fish waste into nutrients
for the plants, and without this process, the
water quality would deteriorate rapidly and
become toxic to both the fish and plants.
Nitrogen gas (N2) is 78% of the atmosphere, and
plant and animal cells need nitrogen to produce
proteins, nucleic acids, and amino acids.
Nitrosomonas bacteria converts ammonia (NH3)
into nitrite (NO2) and then the Nitrobacter
bacteria converts the nitrite into nitrate (NO3).
Nitrate is a very accessible nutrient source for
plants.

7. 5 AQUAPONICS SYSTEM
Variety of Aquaponics
designs that are used in both
commercial and hobbyist
settings.
The most common systems
in usage.
 NFT (Nutrient Film
Technique) – used mainly
in hydroponics
 Flood & Drain system –
(most common hobbyist
system)
 Raft system – (most
common in commercial
systems)

8. 5.1 NFT (NUTRIENT FILM TECHNIQUE)
NFT can be hobbyist or
commercial, but is the
least commonly used
with aquaponics.
The plants are placed in
pots and a small amount
of water (or a film of
water) is trickled through
the base of the channel
from which the roots
access the water.
Can be layered vertically
and wall space can be
used. It can also be
extended very easily and
is the lightest in weight.

9. 5.2 FLOOD & DRAIN SYSTEM
Most common design
used in hobbyist
systems.
Grow bed filled with a
‘grow media’ normally
consisting of either
gravel or clay pebbles.
Plants are planted
directly into the media.
The grow beds are
flooded and drained
periodically, allowing
water to circulate through
the system on a regular
basis.

10. 5.3 DEEP FLOW OR RAFT SYSTEM
Deep flow/raft is mainly
used for commercial or
larger systems. The grow
beds are essentially long
troughs of water, the plants
sit on rafts made from
Styrofoam with holes for
pots to allow the plants to
sit with their roots
immersed in the water.
Restricted to salad
vegetables as the weight of
larger plants such as
tomatoes and cucumbers
cannot be supported easily
on the rafts.

11. 6 ADVANTAGES OF AQUAPONICS
Enabling self-sufficiency
 Providing household self-sufficiency of fruit and vegetables.
Conservation of water
 Maximum water conservation due to water reuse and recycling.
Efficient use of land
 Elimination of need for agricultural land to produce similar crops.
Preserving the environment
 The overall reduction of environmental footprint for crops.
Natural fertilisation
 Organic fertilization of plants with natural fish emulsion.
Low Maintenance
 Aquaponics is very low maintenance compared with todays
ground Agriculture, Horticulture, and Aquaculture.

12. PRACTICAL HOME AQUAPONICS SYSTEM
Can provide the average sized family with fresh leafy vegetables all year
round, with the possibility of one or two edible fish per month as well.