Aquaponics offers fresh way to grow veggies
IT WAS a big turnout at the Port Alfred Garden Club last Tuesday where Martin Fick of HPA (Home-grown Practical Aquaponics) discussed the mechanism and benefits of aquaponics – growing vegetables and other foodstuffs without potentially harmful chemicals.
Fick began HPA eight years ago in Salem.
“My job here is to demystify aquaponics,” he told the audience, adding that the techniques are fairly simple and mirror what happens in nature.
Aquaponics is a methodology that allows plants to grow using bacteria to purify the water that will feed and hydrate the plants through nutrient transfer from fish faeces, sunlight and gravel.
Although the science behind the aquaponics process may seem complex, the same process occurs naturally in the wild. It is dependent upon the circulation of water through the system, where syphoning is used in order to make the process as energy-efficient as possible. Aquaponics relies on two systems, an environment for fish to swim and grow, and a grow-bed, where the plants are grown and harvested.
These two systems are connected via a pump system which takes water from the fish tank to the grow-bed.
Bacteria in the fish tank convert fish faeces and undigested food into ammonia, and then into nitrites. Once pumped to the grow bed, bacteria turn the nitrites into nitrates (naturally-occurring nitrogen-based plant food), and then the now clean water is returned to the fish tank.
Although HPA has built many large-scale aquaponics systems in South Africa and, in fact, around the world, Fick said that small-scale systems are both possible and practical.
“It is possible to create your own aquaponics system, but we have spent the last eight years perfecting our systems,” said Fick.
“These systems are tried and tested here in the Eastern Cape. They are modular and can therefore be up-scaled as required. Although they only use about the same amount of electricity as a light bulb, even this can be negated by the installation of solar panels or wind turbines to make the entire system self-sufficient.
“The outputs are chemical-free high-yields in terms of plants (including flowers) as well as quality fish protein for very little effort and virtually no cost.”
One of the major advantages of the system, according to Fick, is that there is no algae build-up and therefore the fish produced remain algae-free.
Fick explained that it was important to break away from processed foods with its added salt, monosodium glutamate and other additives that can potentially cause health problems.