MODULE 3- AQUAPONICS DESIGN COURSE
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PLUMBING PARTS
MODULE 3- AQUAPONICS DESIGN COURSE
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FLOMEDIA AQUAPONICS SYSTEM
The FloMedia system, devised by Murray Hallam, is
a method of combining Deep Water Culture (DWC)
and media beds, into an homogenous unit. It utilises
the CHOP2 (Constant Height One Pump) operating
system. It provides the ideal balance between DWC
and media beds, providing excellent nutrient for the
plants. Nutrient conversion, production and delivery
are maximised in FloMedia systems, all while delivering excellent water quality. Fruiting plants like tomatoes are grown in the media beds and greens in the
raft beds. The ratio of growing area Murray has found
over time to be ideally 1 media bed : 6 raft beds, by
area.
SWIRL FILTER
Water is taken in from the bottom of the fish tank by
a pipe that outlets to a swirl filter. A swirl filter allows
for the very large particles to settle out. It leaves only
fine suspended particles in the water. Almost any tank
can be used as a settlement tank. Some people use a
clarifier which is really just another version of a settlement tank device.
The base of the outlet pipe in the fish tank.
MODULE 3- AQUAPONICS DESIGN COURSE
It has been shown that the water needs 20 minutes
to travel through the settlement tank in order to be
effective. For example, if you were to have a 1000
litre ( 265 gal ) swirl filter or settlement tank, then the
maximum flow through that device would ideally be
3000lph (795 gal). There is some latitude in these figures. For example, a swirl filter is more efficient than
just a settlement tank, so more water can be sent
through a swirl filter per hour, than through a simple
settlement tank. It is advisable in a commercial setting, to employ a swirl filter or settlement tank to collect the majority of the solid material, to keep down
the solids processing load for the media beds. This
extends the maintenance cycle of the media beds.
The filtration of solids, both large and small is an
ongoing, continuous process. With each pass through
the swirl filter or media beds, more fine solids are
picked up and processed.
The fish tank and the swirl filter tank are level. The
swirl filter outlet sets the water level of the fish tank.
Water then flows into the sump from the swirl filter.
Energy consumption is kept to a minimum by utilising
one pump in the sump which operates continually
pumping water up to a header tank. The pump needs
to be of sufficient capacity to move the water from
the sump up to the header tank , keeping it full. The
header tank is usually situated directly above the
sump. This allows the gravity distribution of water
through out every part of the system.
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MODULE 3- AQUAPONICS DESIGN COURSE
The term we use to describe this balanced
design criteria of two stage filtration and
mineralization is FloMedia
FLOATING RAFTS
MINERALISATION TANK
Mineralisation of the solid material extracted from the
swirl filter occurs in the mineralisation tank. Sludge
from the bottom of the swirl filter is drained into the
tank when the need arises. Vigorous aeration is applied, creating an oxygen rich environment for bacteria to process the nutrients, otherwise trapped in the
solid material.
Periodically the air is turned off, the solid material is
allowed to sink to the bottom of the tank and the nutrient rich water is drawn off by gravity, back into the
sump. It is then combined with the nutrient stream
onwards to the plants. When the mineralization tank
has reached a half full of settled solids, the spent solid
material needs to be removed and the mineralization tank completely cleaned out. This spent material
is placed into the farm composting process. There
should be no waste of fish solids. All possible nutrient
value is returned to the system.
MEDIA BED
A media bed carries out three major functions in a
well designed Aquaponics system.
It acts as a solid separation filter. That is it collects solid particles from the water by mechanical screening.
Sheets of styrofoam are used for the floating rafts in
the DWC beds. Ideally the rafts should be 50mm/2
inches thick to hold the weight of the plants. Spacings of 200m (8 inches) between plants is suitable
for lettuce. If the netpots are 40mm, a 50mm hole
is drilled. This allows for air around the plants, which
promotes root growth. If you have a number of
sheets floating together, marking a drill hole point
100m from the edge of the foam, will give you the
200mm allowance needed, when the sheets are put
together.
Seedlings can be planted out in each hole initially and
as they get bigger some are lifted out and transferred
to another raft bed. This allows the plants to grow
out to their optimum size.
Both the media beds and floating raft beds are lined
LDPE (low-density polyethylene). In the USA it is
know as Durascrim. It is recommended that a double layer be used in the media beds because of the
possibility of puncturing the material with the gravel
when loading the beds and possibly when maintaining them. The Durascrim liner is available in 100 ft x
6 ft wide rolls. This will affect the dimensions of your
beds and needs to be considered in your design.
It acts as a bio -filter. That is, dssolved ammonia is
converted to nitrate.
It acts as a solids mineralization area. That is, solid
material is broken down into nutrients by microorganisms present within the beds.
The balance between the fish tank,primary filtration ie
the swirl filter, media beds and raft beds needs to be
correctly proportioned, in order to achieve optimum
performance of the entire system.
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SEED SAVING
MODULE 3- AQUAPONICS DESIGN COURSE
Only heritage seeds can be saved. Hybrid seeds will
not remain true to type. Choose a plant variety which
is suited to your location. Allow the healthiest plant
in the crop to go to seed or pick fruit like tomatoes
from the best plant. Over a few generations you will
have seed that is adapted specifically for your location. Beans, tomatoes, lettuce and peppers are self
pollinating so there is less risk of cross pollination and
they are easier to save. Separate plants that do cross
pollinate. Or grow early, mid and late flowering varieties with flowering times that don’t correspond.
The Seed Savers Handbook is a great resource
on how to save over 117 food plants.
For tomatoes choose the best tomatoes after they
have ripened and scrape out all the seeds. Put them
in a jar and let them ferment for 3 days to remove the
gel around the seeds. Stir every day. A layer of fungus
will grow over the seeds which breaks down the gel
and also assists in resisting disease. After 3 days put
the seeds in a bigger container, add water and strain
off the pulp. The seeds will sink to the bottom. Dry
the seeds on a flat surface moving them around so
they don’t clump as they dry.
Seeds from peppers can just be taken from the ripe
fruit and dried in the sun.
Lettuce seed heads are like capsules each containing
a seed. When they start looking dry, cut the top of
the lettuce and it put in in a paper bag upside down
and leave it to dry. The seeds will fall out when they
are fully dried, into the bag. You can put the seeds
through a colander which has holes big enough for
the seed but small enough to keep the chaff out, or
winnow of the chaff.
Always label the seed with Variety, Date and the Location. Store them in a dark, cool place. Viability times
differ from plant to plant but generally use the seed
the next season.
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SMALL PINE KIT MATERIALS
MODULE 3- AQUAPONICS DESIGN COURSE
The Small Pine Kit is an ideal home system. Follow
the build with the video lessons in module 3.
It is a great first project to build and operate so that
you can really understand in a practical way the
fundamentals of Aquaponics. It is advised to do this
project and run it for a period before you embark on
bigger systems.
TIMBER
Pine – 90mm x 35mm 1130mm long x 34
730mm long x 4
310mm long x 2
Ply
1200mm x 1130mm x 12mm x 1
Decking Timber – 90 x 20mm
1300mm x 11
POND LINER
5m x 2m- HDPE is food safe as is Dura Skrim liner
POLYSTYRENE
1000mm x 1100mm x 50mm x 1
PUMP
3000 – 4000 lph pump with male snap on fitting x1
Venturi for fish tank inlet OR air pump (9lpm) x1
SCREWS
65mm philips pine screws x 150
35mm philips pine screws x 50
Nails clout 25mm x 50
FISH TANK 300 – 400 ltr x 1
PIPEWORK
19mm Flexi hose – 5m x 1
Hose clamps for 19mm hose x 20
Tap x 2
Barbed T x 2
*Snap on female straight x 2
*Snap on Female elbow x 1
*Double nut fitting x 1
*Snap on male to 25mm threaded male x 1
*25mm Through tank fitting x 2
*Auto siphon x 1
25mm PVC – End Cap x 1
T x 1
Socket adapter x 1
Faucet adapter x 1
90 deg elbow x 3
1m length of pipe
BUILDING OFF THE GROUND
Building media beds and raft beds up off the ground
makes it more comfortable and efficient to plant and
harvest. In a commercial system especially, the ergonomic design of operation makes it easier for workers
and therefore more efficient.
Raised beds also have fewer pests and it is easier to
control them.
Height is also needed to gravity feed water into sumps
in some designs.
The disadvantage is, it is more expensive to add
height to beds and they do need solid foundations
because of the weight. However the advantages of
building above ground height make it well worth the
investment.
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