Aquaponics is a grand endeavor, but it’s not for the faint of heart.
Bryan Wood, owner of Central Texas Aquaponics, in Weir, Texas, has faced many
hurdles, triumphs, and tragedies, and much excitement, in the short time he’s had
his aquaponics greenhouse. It’s a business that constantly requires his attention and
focus, even when he’s not in the greenhouse.
Hydroponics vs. Aquaponics
While hydroponics and aquaponics may be a bit similar, the difference between
them, really, is the fish. Both methods grow produce in water, without the use of
any soil. However, hydroponics uses nutrients that are typically from a non-natural
source. Over time, you’ll need to dump the water used in hydroponics because the
water becomes oversaturated with nutrients and must be refreshed.
In aquaponics, the nutrients for the plants are provided by the fish waste that runs
through the pipes and filters (the filters help keep out any fish eggs or “fry” that might
get sucked into the pipes by accident) all the way to the plant beds. The fish waste is
high in nutrition that the plants need to grow healthy. When the water runs through
the beds it feeds and waters the plants at the same time. There is no wastewater to dispose of and the water can be used repeatedly as it cycles through the system.
There are two components to aquaponics:
fish and plants. First, let’s focus on the fish. It
turns out you can use tilapia, blue gill, trout,
bass, catfish, and even koi. Bryan chooses two
different fish: tilapia and catfish.
Tilapia grow fast and are a mild-tasting fish.
“We wanted a protein source that we can eat
and that can sustain itself. They can breed easily, with just a few requirements. Plus, they’re
fun. When you feed them, they explode. It’s a
shark-feeding frenzy.” Since tilapia is considered an exotic fish in the state of Texas, those
who want to grow and harvest tilapia must
receive permission from the state and the
state will inspect “to make sure they don’t get into a waterway.” After all, “Texas waters are warm enough; they could start displacing populations” of indigenous species.
They are also an extremely healthy fish, easy to grow, and very hardy (“except for the
temperature thing,” Bryan said).
Catfish are native to Texas, plus they don’t need an oxygen tank if you have a large
enough tank and you don’t overstuff it with fish. They don’t care about the temperature of the water and they are hardy. They eat well and, while “tilapia slow down in
winter, catfish do not. They don’t care how cold the water is,” Bryan said. Channel
cats can get up to 40 pounds in size. “They eat all the time. You decide how much
you want to feed them.” Bryan says that tilapia will eat until they get full, but catfish
constantly eat and therefore grow to a larger size.
If you are considering an aquaponics system for your family, you can typically plant
the same things you would if you were gardening in dirt. Stick with what grows in
your region and you should be fine.