At Chimney Rock Farms on the Piedra River, Brewer has built two commercial-scale aquaponic greenhouses that house fish tanks and thousands of square feet of troughs where kale, lettuce and tot soy float on a foot of water in rafts from seed to harvest.
“We’re pioneering this, no doubt,” said Brewer. He said that the operation, located 6,600 feet above sea level, is the largest commercial aquaponics farm venture in Colorado.
Brewer plans to supply new Southwest Farm Fresh, A Farm and Ranch Cooperative, which was started in Montezuma County. He also plans to supply the Pagosa Springs farmers market, his Community Supported Agriculture membership, organic grocery stores and restaurants.
In March, the operation had already been supplying a grocery store for three weeks.
In the aquaponic environment, the greens mature in six weeks, which allows him to provide custom mixes of greens and meet demand quickly.
“It’s revolutionary for us,” he said.
In addition to greens, his tilapia – the “aquaponic” aspect of the hydroponic system – can also be sold. Brewer may sell the fish whole on ice at farmers markets, but they are not his main focus.
How it works
In the most basic terms, fish poop feeds plants. In technical terms, the tilapia excrete ammonia. Bacteria break the ammonia down into nitrites and then into nitrates, which feed the plants. The plant roots filter the water, and the water is pumped back to the fish.
The tilapia can’t be kept with the plants because they’d eat the roots. But very small mosquito fish clean the roots and fend off potential mosquitoes.
The seeds are germinated in soil, and the fish-fertilized water flows beneath. As the plants mature, they are transferred into rafts that allow for more space and push down the trough. This system reduces man hours and eliminates all weeds.
“We were spending 60 percent of the time to produce a leafy green, weeding our beds,” he said. To harvest, the roots just need to be trimmed off.
It is also very efficient in terms of water. Aquaponic systems use less than 5 percent of the water of traditional agriculture, Brewer said.
“This is a good fit for us in the desert Southwest,” Brewer said.
As green as possible
Brewer was looking for ways to grow year round, but the inefficiencies of a greenhouse held him back.
“Heating traditional greenhouses with fossil fuels – propane and natural gas – is a very, very tough way to make a living,” he said.
In his newly built greenhouses, the water is heated by solar panels, and a wood boiler. This allows him to grow when temperatures are below freezing outside. He also uses solar panels to power air and water pumps, and grow lights. The solar panels allow him to put electricity back into the grid, and his monthly electricity bill has dropped from more than $600 to just $16.
In the new greenhouses, he hopes to grow from mid-February through Thanksgiving.
He expects that he will make back his investment in his capital improvements in five to six years.
It was important to him to reduce his use of fossil fuels because they are limited resource and their ballooning costs can cut into thin farm profit margins.
“As a farmer, your margins are too thin to rely on fossil fuel costs as a line item,” Brewer said…
“Hopefully, we can prove the economic viability of this such that other people are willing to take the capital intensive risk to build a system like this to grow local food,” he said.