A few weeks ago, the writer of this article featured online communities that are engaged in urban farming, especially those in Metro Manila. Last week, one of said urban farms was visited.
Mr. Gerry Antonio is an Industrial Engineer by profession. Now retired, he focuses full time on his personal projects. He is upgrading his farm in Davao and also gives time to his hobby, aquaponics, which is the convergence of aquaculture and hydroponics. In layman’s terms, this means one grows fish and plants together in a recirculating system.
In that system, the fish produce the nutrient source through wastes, the plants utilize (and in the process remove) the wastes that first start off as ammonia and then, through nitrification thanks to beneficial bacteria, becomes nitrites and finally nitrates. The latter, unlike ammonia and nitrites, is generally not harmful to fish and is a good source of nutrients for the plants.
During the visit, Gerry shared that he started out early with aquaculture. As young as 8 years old, he was into fish already. And this interest of his has guided his lifetime’s worth of work.
For example, his setup at his residence is full guppies, fighting fish, as well as tilapia. For the ornamentals, Gerry breeds them for a hobby and sells some to pet shops. He also competes internationally and has won recognition for his skills as a fish breeder.
He also grows his own feeds, and not just duckweed, but also micro worms and living freshwater cladoceran crustaceans called Moina (sometimes Daphnia). The fish love to eat these.
Interestingly, his fish tanks are generally without aerators, but with aquatic plants submerged below the water line. Also, to provide for water exchange, as well as to level different tanks, he uses a simple hose with each end touching the bottom of two separate tanks. The natural siphon effect moves water from one tank to the other without any mechanical parts of pipe connections. “Keep it simple,” he would often quip.
As for the other side of the equation, the plants component, Gerry grows some greens. The nutrient-rich water from the fish tanks allow for the growing of pineapples (on the roof, yes, he has pineapples growing up there), and he also grows mint, ginger and a flowering plant called blue ternatea. The latter is used to add color to rice or brewed separately and served as a highly effective relaxant drink.
Gerry also has aloe vera growing in PVC pipes. In other countries, utilization of aquaponic technology for growing plants for cosmetic purposes is gaining ground. The attraction stems from the fact that one cannot use harmful pesticides in an aquaponics setup (you end up killing the fish). People prefer to keep their cosmetic ingredients pesticide-free.
The setup that Gerry has is still evolving. Presently, he’s fixing old aquariums. He’s also making new concrete tanks. And his farm in Davao is upgrading.
A true patriot, he hopes that the next generation of his kababayans will continue with building and improving aquaculture and agricultural technologies. He’s doing his part as he shares what he knows to the younger ones. By doing so, much hope is still there for the Filipino nation.