Because the climate, soil quality and pests in Panaga present challenges for vegetable gardening, it should not have surprised me to learn that several households are taking a crack at aquaponics, the environmentally friendly food production technique touted to work pretty much anywhere. However, what little I knew of aquaponics seemed super complicated, so I was indeed surprised. And impressed. And I had to know more.
But let me back up. You might be wondering, what is aquaponics?
Aquaponics combines aquaculture (fish farming) with hydroponics (the cultivation of plants in water instead of soil). These two activities, on their own, have some drawbacks that virtually disappear when you put them together. Fish waste and uneaten fish food release ammonium, so the wastewater from aquaculture is a pollutant. Hydroponics, on the other hand, requires fertilizers that are expensive and must be constantly replenished, and the wastewater can also be a pollutant. However, in a very circle-of-life way, aquaculture wastewater is the perfect fertilizer for hydroponic gardening.
But what does it look like to put them together? Ankur Singh was gracious enough to take me on a tour of the two aquaponic gardens he’s cultivated over the past few years—one in his backyard and one in his carport. There are variations on how to do it, but the concept is simple. The fish live in a tank, swimming around and producing wastewater. Water from the tank is pumped into a grow-bed for plants. Bacteria in the grow-bed turn the ammonium into nitrites and then nitrates, which are plant food. The plants clean the water as they grow big and strong and produce lots of healthy food for humans, and the clean water is flushed back into the fish tank to freshen the water for the fish.
Once I sort-of-kind-of understood the process, I had to ask what inspired Ankur to take up this elaborate hobby. He said it started with some disappointed attempts at container gardening, which he’d enjoyed in Bangalore where the weather is cooler and drier—much more conducive to gardening—than the heat and abject humidity of Brunei. After trying to grow vegetables in Panaga, he was discouraged by how much effort was required for such a paltry yield, and he decided to give aquaponics a try.
“I like fish and I like gardening,” he explained, “so why not put them together?”
The first stop on my tour was the intermediate bulk container (IBC) system he has set up in his carport. It looks more like privacy landscaping than a laboratory, especially from the outside. There is a tank for the fish, some tubes pumping water into the grow-beds, and a bell syphon to flush the water from the grow-beds back into the tank. The bitter gourd, cucumbers, mint, and pumpkin are flourishing.
Whereas this IBC system is a relatively compact, plant-heavy version of aquaponics, his backyard set-up is much larger and, when I visited, very fish-heavy. He had recently pulled up most of the plants in an attempt to handle an infestation of ants and white flies (more on this later). Before that, judging from his harvest records, it was a veritable aquaponics farm back there. At one point he was getting 4 to 5 kg of ridge gourd EVERY DAY, which is obviously more than he and his wife and all their friends could consume. Even after pulling most of the plants, the pak choy, betel leaf, and lemon balm crop make the backyard lush and green. Still, there aren’t enough plants there to keep the water clean for the fish, so he transfers the water once or twice a week to the carport IBC system, where the plants can use the extra food.
Speaking of the fish: In the large, concrete tank in the backyard, there wasn’t much to see until Ankur threw in a handful of feed. The water started churning as the fish rushed to get a snack. Though hardly cuddly, their get-up-and-go made them pretty endearing. A few minutes later Ankur threw in a scoop of duckweed (“It’s their salad,” he said), which didn’t generate quite as enthusiastic a response. Maybe they were full.
Ankur’s focus is more on the vegetables, the fish being quasi-pets, and he seems to enjoy the chemistry aspect of monitoring the levels of Ph, nitrates, nitrites and ammonium in the water. For other Panaga aquaponics enthusiasts like Shalini Lopez D’Costa, the interest is somewhat reversed.
Shalini and her family acquired their aquaponics system from a family who was leaving Panaga, and Shalini said it was simple enough to transport and set up. Their system uses both the nutrient film technique (NFT) and media beds, and they’ve had success growing betel leaf, two types of mint, pak choy, and lettuce. They’re also working on honey melon and papaya, but the family mostly enjoys the ready supply of fresh fish to eat.
Of course, because this is the jungle, the family has had some competition for the fish from other local carnivores. When a monitor lizard started making itself at home in the family’s garden, the family assumed it was just sunning itself.
It was not.
“A few days in,” Shalini remembered, “I noticed it carrying away one of the large tilapia. That’s when we realised it was there for the fish… He probably managed only two large fish over two days, but we had a few fish that were traumatized by the whole thing and died a few days later or committed suicide by jumping out.”
Undeterred, Shalini and her family figured out how the lizard was getting at the fish and took measures to deny access. Still, Shalini said, “it took a lot of scares from the children, amah, Louis and myself to get them to realise that the fish weren’t theirs!”
My takeaway is that cages or screens might be necessary to protect the fish from predators and the vegetables from monkeys, but Shalini also had some advice for handling the smaller, insect-level pests that can harm the plants. Because the three systems—fish, plants, and bacteria—are interconnected, pesticides on the plants will harm the other systems and are, perhaps, against the spirit of things. (This is also true of conventional food production methods, but in those, it’s easier to ignore the literal and figurative downstream effects of pesticides and fertilizers.)
There are some solutions for handling some pests, but in aquaponics, there’s always the nuclear option: “submerging the media beds in water for a day or so… and repeating if necessary,” Shalini suggests. This is what Ankur had to do, though he didn’t sound too upset about taking a break from ridge gourd.
This might sound intimidating and complicated, but cultivating fresh food at home is viscerally appealing, and apparently it’s catching.
After seeing Shalini’s set-up, Thomas Lassaigne was intrigued by the elegant simplicity of the system, especially its low-tech gizmos like the bell syphon. Earlier this year, he found himself in possession of a pile of wood from a house extension he’d had dismantled, which was perfect material for building the tank and grow-bed. The final push was a batch of tilapia babies that Shalini’s family was looking to offload, which roughly coincided with the borders being locked down due to COVID-19.
Thomas acknowledges that the weekends at home, which if not for COVID would probably have been spent traveling, gave him more time for the project. And though the initial outlay of effort might seem onerous to some, Thomas got a lot of satisfaction from building the structure, especially because it was a family affair. His kids, Louis and Alice, along with some of their friends, made the fish tank their own by painting sea creatures on the sides. They also have a couple of pet koi living among the tilapia.
Thomas is still in the early stages of setting up the system, which gave me the opportunity to see the different components before they became hidden by flourishing plants. It also offered a different perspective on the whole process. Rather than focusing on the chemistry of the operation, Thomas is hedging his bets. When I visited, half of his fish were living in the outdoor tank and the other half in an aquarium in the living room. He had the grow-bed half full of gravel and was waiting a bit before pouring the rest. A few days later, he had some seed starters ready to go.
He said that sourcing the materials for the system was pretty straightforward. The tubing (food-grade PVC), the water pump, the air diffuser (or bubbler), the fish, the food, the seeds, and the testing kits are all available locally at various shops in KB and Bandar. Thomas ordered the fish tank liner from China because he couldn’t confirm that the used ones sold here were not contaminated with chemicals. (Brand-new fish tanks are available in Bandar, but they are, obviously, more expensive than reclaimed wood and elbow grease.)
Though Thomas still has a bit of work ahead of him, Ankur explained that most of the effort and expense of aquaponics is frontloaded, during set-up. It takes about two months for the necessary bacteria colony to develop, and after that, the system is about as hands-off as a garden can be. The two main inputs are food for the fish and water to replace what is lost to evaporation through the plants’ leaves. (Ankur uses tap water, which he keeps in tubs so the chlorine can evaporate.) The electricity required to pump the water is roughly the amount used by a lightbulb or two, which is negligible compared to the energy required to cultivate and ship conventionally grown produce. You have to monitor the Ph, nitrate and ammonia levels monthly or as needed, and, of course, you have to plant and harvest the produce, but that’s about it.
As with any elaborate project, the devil is in the details, and mistakes are inevitable. Ankur admitted if he could do it again, he would reverse the position of his backyard fish pool, which gets a lot of light, and the grow-beds that are in the shade. This is obvious only after the fact, and he got so many vegetables anyway that he seemed not at all regretful. Even Shalini’s monitor lizard episode seems more like an amusing anecdote than a cautionary tale against the whole endeavor.
Unsurprisingly, aquaponics is not an instant-gratification pastime, though neither is conventional gardening. However, the paradigm for how we spend our time has definitely shifted. Thomas reflected that his folks at home in France were also getting a bit more “back to basics,” with hobbies like gardening, as a result of the pandemic. For us here in Panaga, where traveling was a way of life, it made little sense to invest time and money in projects that would surely be neglected before they even got off the ground. Now that travel options are limited for the foreseeable future, the weekends ahead might look like a protracted yawn. But maybe there’s some crazy undertaking, like aquaponics, that can provide the satisfaction of putting down roots, even if those roots happen to be in water.
*This article was originally published in the September-October 2020 issue of Panaga Outpost Pages, a community newsletter in the Belait district of Brunei Darussalam.