What is aquaponics?
Aquaponics combines two farming methods which are aquaculture and hydroponics. Aquaculture or aquafarming is the cultivation of fish, crustaceans, algae, and other aquatic animals in a controlled aquatic environment while hydroponics is the method of cultivating plants without the use of soil by using mineral nutrient solutions in a water solvent. This agri-farming system combines two methods and supports a symbiotic relationship for the plants and fish wherein fish waste feeds the plants while the latter purifies and filters the water for the fish.
How does aquaponics work?
Before discussing the pros and cons of aquaponics, here’s a little discussion on how this farming system works. As mentioned earlier, there’s a symbiotic relationship among the plants and fish that are cultivated in this farming system. The excretion from the fish acts as natural fertilizer and manure for the plants and it contains minerals like potassium, nitrogen, phosphorus, and ammonia which are converted into nitrates. Fish manure is distributed to the water basins through a pump.
Other supplements and plant food may be given to supplement the nutrients such as iron and calcium which helps further in purifying the water. To avoid contamination due to overproduction of ammonia, roots and certain microbes help convert it to nitrates that feed the plants.
These are the four basic components of an aquaponics system:
- a fish tank or aquarium
- a grow bed for plants
- a water transport method such as a water pump to distribute water from the fish tank to the grow bed
- a method using pipes or siphons to drain the water from the grow bed back into the fish tank
Pros and cons of aquaponics
Just like with other types of farming methods, aquaponics has its share of pros and cons:
1. It is environmentally-friendly.
The aquaponics system doesn’t use artificial fertilizers and pesticides that can harm and kill the fish which makes it environmentally safe. Compared to land-based farming systems that claim they only use organic techniques but tend to use harmful composts, aquaponics doesn’t use components that harm the cultivated plants and fish.
2. It saves water.
Water is effectively recycled and reused and there are an estimated 80 to 90% water savings with the farming method. This is equally helpful especially if you live in a place where water is precious and scarce.
3. It has a high level of nutrient utilization.
The cultivated plants as well as the fish being cared for in an aquaponics system utilize supplement contribution through the fish food and there’s no need for artificial supplements that could harm the fish and plants. There is no form of waste and solids collected can be added to compost or applied in berry bushes. Unharvested plants from the aquaponics system can be composted or fed to animals and very little water is discharged.
4. It’s affordable and easy to maintain.
While some people may be initially put off by the expenses that come with the system set-up, aquaponics is actually an affordable farming method. You don’t have to purchase synthetic fertilizers aside from the amount of water that is saved since it’s recycled. The farming method mimics a natural ecosystem where nutrients are produced without the need for chemicals and pesticides that cost money. Similarly, aquaponics is easy to maintain and you just have to understand fully the basics of the system. School children can be taught about the system and schools are introducing it as part of their STEM subjects like Biology, Chemistry, and Engineering.
5. It’s space-efficient.
What makes aquaponics very ideal is the fact that you can already grow your food and fish even though you only have an aquarium or just a few square meters worth of space in your backyard for the grow beds. It’s practically a soil-less method so space is efficiently saved. Whether you’re living in an urban area or high-rise building, it’s still possible to start your aquaponics system and be able to enjoy fresh and healthy food produce all year-round. Also, the farming method can be done regardless if you’re living in a hot temperature region or a place with chilly weather. Since it can be done indoors, it’s not affected by weather or climate.
6. It reduces food miles.
Having your own aquaponics system in your backyard reduces transportation expenses and “food miles” since you don’t have to travel to the supermarket to buy food. By growing your own vegetables and fish, there’s also fewer chances of spoilage and other food safety concerns and you’re assured of good quality and healthy food.
7. It’s a good source of income.
A backyard and small-scale aquaponics system are more than enough to feed your family, thus, you could also venture to sell some of the vegetables and fish during harvest time. It could be a good source of income and your customers are only assured of fresh and healthy food that is free of synthetic fertilizers and chemicals.
1. Not all crops and types of fish are feasible for the method.
If you’re fond of root crops then it may dismay you because root crops along with tuberous plants cannot thrive with the aquaponics system. These types of plants such as potatoes, cassavas, and sweet potatoes need soil to grow. Nevertheless, there are many vegetables that you can easily cultivate with the method and these include cabbage, lettuce, kale, spinach, beets, radish, broccoli, cauliflower, watercress, mint, basil, and chives. Recommended types of fish include tilapia, catfish, koi, carp, and bluegill.
2. It can be costly.
Some costs need to be handled if you’re starting your own aquaponics systems and this includes water tanks, grow beds, fish fingerlings, plant seedlings, and equipment to manage the water distribution system. Another big chunk to the cost is the monthly electric bill that’s incurred. However, there are other alternative energy sources that you can consider to cut expenses such as solar energy, wind, and hydroelectric power.
3. There’s high consumption of electricity.
Electricity is essential in aquaponics because water pumps need to operate round-the-clock and temperature in the fish tank should also be maintained. However, it can lead to high consumption of electricity. But this can be addressed by using other alternative energy sources such as solar energy, wind, and hydroelectric power.
4. It must be professionally installed.
While this farming method can be easily learned even by schoolchildren, it requires to be professionally installed to avoid losses in capital. An inadequately-constructed aquaponics setup could mean that plants will wither and the fish won’t survive. It’s advisable to seek help from an aquaponics expert to avoid financial loss.
5. There’s a chance of unexpected failure.
As it is with other farming methods, there’s a chance that your aquaponics system may fail if all the conditions are not met. It requires monitoring and extra care because you’re tending and cultivating plants but also seeing to it that the fish are getting the right nutrients and growing well. If the fish are not cared in the right conditions they may die and plants are susceptible to pathogens that lead to diseases.