WHAT IS A DWC SYSTEM?
DWC
HINT:
DWC stands for deep water
culture, a variation of a standard
water culture system. A DWC
system works exactly the same as
a standard water culture system,
the only difference is the water is
deeper than a standard water culture system. Though many people
refer to any water culture system
as a DWC system, water culture
systems aren’t really considered
“deep water” unless the water is
at least 10-12-in. deep.
The roots hang down from the baskets directly into the
nutrient solution, where they remain submerged 24/7.
The reason they don’t suffocate is because they get
the air and oxygen they need from air bubbles rising
through the nutrient solution, as well as from dissolved
oxygen in the water itself.
In a water culture system, the more air bubbles the
better. There should be enough rising bubbles to make
the water look like it’s boiling at a heavy, rolling boil. The
bubbles should be rising up through, and making direct
contact with, the roots as they rise to the top of the water
to be most effective for the plants. There are two ways of
providing aeration and dissolved oxygen to the nutrient
solution: air bubbles or falling water.
AIR BUBBLES: An aquarium air pump and air stones
are typically used to provide air bubbles to the nutrient
solution for water culture systems, as well as other types
of hydroponic systems. The air pump provides the air
volume, and is connected to air stones with an air line/
tubing. The air stones are made of a porous, rock-like
material; the small pores create small individual air
bubbles that rise to the top of the nutrient solution.
A soaker hose, which creates even smaller bubbles, can
be used in place of air stones as well. The smaller the
air bubbles, the better they are for aerating nutrient
solutions, as smaller air bubbles provide more contact
68
Maximum Yield USA | December 2015
“AN AQUARIUM AIR PUMP
AND AIR STONES ARE
TYPICALLY USED TO PROVIDE
AIR BUBBLES TO THE
NUTRIENT SOLUTION FOR
WATER CULTURE SYSTEMS.”
surface with the water. The contact between the air
bubbles and water helps replace the dissolved oxygen
taken up by the plants’ roots.
FALLING WATER: Though not typical in at-home water
culture systems, surface agitation from falling water
splashing around is another good way of aerating the
nutrient solution. The higher the water is falling from,
and the more volume of water falling, the more downward force it has when it hits the water’s surface. The
more downward force, the deeper the agitation and the
more dissolved oxygen provided. This method of aeration
is more common in commercial water culture systems
because they use larger volumes of water than what home
growers use.