by Ray Barkalow
A Simple Water-Saving
HYDROPONICS SETUP
I was approached by a missionary on a remote Ca-
ribbean island to help design a simple hydroponics
setup for growing vegetables. Most of their food
needed to be shipped in, making it unreliable and
expensive.
Their potential system had two major constraints.
One was that the system needed to conserve water,
primarily through limiting evaporation, and the sec-
ond was that it must have low power consumption,
due to the need to use solar panels to generate the
needed electricity for pumping.
Single-pot semi-hydroponics was a reasonable start-
ing place, but that presented some issues when it
came to distribution of nutrient solution to the pots,
and collection of the runoff for recirculation. Instead,
we opted for the use of a connected series of PVC
pipes that acted both as the growing containers, as
well as the distribution and collection system.
The “entry end” of the pipes were capped and then
drilled to accept tubing for delivery of the nutrient
solution. The “exit end” of the pipes were connected
via TEES to create a collection manifold. The collec-
tion manifold gravity drained into a 55-gallon plastic
drum used as a sump. The growing chambers were
fi lled with LECA growing medium.
A 12-volt submersible pump, powered by a car bat-
tery that was recharged by a small solar panel, was
placed in the sump, and its output was directed into
the entry ends of the growing chambers.
The illustration with this article is a representation
of the setup, looking down from above. The black
The “growing chambers” consisted of 6�, thin wall
PVC pipe (commonly known as Schedule 20 “crush
pipe” in the US, where it is sold for drainage pur-
poses only). With the pipes laid fl at on the ground,
holes were drilled in the pipe on 12�- to 24� centers,
depending upon the crop to be grown, using a 5�
hole saw.
MULTIPURPOSE GREENHOUSE
DISINFECTANT & DISEASE CONTROL
• Disinfect pots, trays, benches, tools, etc.
• Algae control on walkways, pots, evaporative coolers, soil
• Spray on plants to control bacterial, viral and fungal disease
• Excellent wetting agent
• Cost effective, pleasant odor and environmentally friendly
MARIL PRODUCTS, INC.
15421 Red Hill Ave. • Suite D • Tustin, CA 92780 USA
714-544-7711 • 800-546-7711 • www.physan.com
36
www.GardenandGreenhouse.net
July 2019