autodosers
OVER THE COURSE OF A
GROW CYCLE, an autodoser can
free up many hours of the grower’s time
and the gardener may choose to spend
that extra time increasing the efficiency
of other areas in his or her garden.”
Each autodosing system is a little different, but
the most common set-up is a system that can
handle four different solutions for injection. This
is likely because the most common hydroponic
nutrients are still three-part (micro, grow, bloom)
solutions. An autodoser that can handle four
different chemicals is able to administer a
three-part fertilizer, plus one pH buffer solution.
Typically, a hydroponic gardener will use only
one pH buffer solution because the pH of a
hydroponic nutrient solution tends to drift in only
one direction. Although systems set up to handle
four chemicals are the most common, there are
autodosing systems that can administer up to
eight different chemicals.
PUMPS/INJECTORS
The pump or injector is the component of an auto-
dosing system that pumps or injects the nutrients
or pH buffer into the hydroponic system’s nutrient
solution. The injectors/pumps are controlled by the
monitor/controller and are triggered by electricity
or by water flow. There are three types of injectors/
pumps commonly used in autodosing systems:
gravity-fed solenoid valves, water-powered injec-
tors, and peristaltic pumps.
Gravity-fed Solenoid Valves
Gravity-fed solenoid valves are injectors that
require the concentrated nutrient to be stored
above the valve and rely on gravity to create the
flow of solution once the solenoid is triggered. The
monitor/controller electrically triggers the solenoid
to open, which, with the help of gravity, allows the
concentrated nutrients to flow into the solution.
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grow cycle