keeping with the flow
In drain-to-waste, the water that is
applied to the growing medium is not
returned to the water-nutrient tank;
instead, it is fed away from the system
into a drain. The fact that some water
is going to be drained off in the drainto-waste system does not mean that
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there will be significant waste of water
or nutrient, however. When designed
properly, this type of system wastes very
little water.
Below is a discussion in which we
look at these two types of irrigation
systems within a soilless hydroponic
setting. Instead
of soil, growing mediums
like expanded
clay, rockwool,
coir, perlite, sand
or gravel, and
other organic
and inorganic
mediums are
used. (Soil generally includes
fine particles
like silt and
clay that cause
medium loss in
“Soil generally
includes fine particles
like silt and clay that
cause medium loss
in a drain-to-waste
or clogging in a
recirculating system.”
a drain-to-waste or clogging in a recirculating system.)
Pros and cons
An obvious advantage of recirculating
water systems is that the extra water
and nutrient applied to the plant’s root
systems is saved and then reapplied to the