There is so much debate surrounding the two soilless agricultural systems sweeping the globe today. Both aquaponics and hydroponics, at first glance, sound a lot similar as both eliminate soil as a medium to grow plants and crops; with the aim being delivering sustainable and profitable food production. But what specific differences do these systems have that made many believe that aquaponics is a better choice?
 Photo Credits: Coastal Mugs |
 Photo Credits: Suburban Farmer |
Here, we are going to unravel the main differences of each system to check if, indeed, aquaponics is the best:
Photo Credits: Inhabitat
In the absence of soil, hydroponics simply makes use of water and chemical nutrients to sustain plant. Considered a popular method of growing greenhouse tomato, basil, lettuce, and, recently, marijuana. Plants are directly grown into specially prepared water-based solution which contains essential nutrients to grow them. This water solution is periodically replaced. Pebbles and clay pellets are sometimes included to support the plants. Hydroponics system has 6 basic types, namely, Wick, Flood and Drain (Ebb and Flow), Water Culture, Drip, Nutrient Film Technique (NFT) and Aeroponic— each of these have hundreds or variations.
Aquaponics
In the simplest of definitions, aquaponics is the improved combination of aquaculture and hydroponics. It involves capitalizing on the benefits of each system and eliminating their drawbacks. There are three main elements to the aquaponics system: the fish, the plants, and the nitrifying bacteria of the worms and microbes. The fish produce the waste which microbes and worms turn into fertilizing agent as organic food source for plants. The plants, in turn, provide the natural water 'filtering agent' for the fish to thrive.
Here’s a tabulation of the advantages and drawbacks between hydroponics and aquaponics:
| Elements | Hydroponics | Aquaponics |
|---|---|---|
| Energy Requirement | Need aerators and pumps | Frequent water circulation leads to higher energy requirement |
Maintenance | Requires frequent checks | Natural ecosystem balances everything; ammonia and pH level checks once a week only while nitrate levels are checked once a month |
| Waste Disposal | Periodic replacement of water-based solution leads to large amounts of waste water; can pose environmental risk. | Solid waste in excess of broken down waste by nitrifying bacteria is minimal and pose no risk to the environment. |
| Cost of Chemical Nutrient | Expensive chemical nutrients | Requires mostly use of fish feed which is cheaper. |
| Risk of Diseases | Risk from fungal infections is higher; An outbreak can spoil an entire batch. | Built in a natural ecosystem thus, resistance to diseases is higher. |
| Nutrient Solution Retention | Periodic unloading of water due to toxicity from salt and chemical build-up. | Has natural balance of nitrogen; water is seldom replaced; topped up only due to evaporation |
| Solid Media | Needs 6-inch deep beds when pebbles and clay balls are used. | Needs 12-inch deep beds of pebbles and clay balls to sustain waste-eating microorganisms. |
| Setting Up | Faster set-up with no required time for gestation period | Requires 3-6 months for the system to be fully functional. |
| Mechanical Failure Risks | No lasting damage | Problems in circulation can adversely affect fish mortality |
| Productivity | Lower returns | Quicker and higher returns approximately after a period of 6 months |
| Organic Growth | Makes use of costly mixture of chemicals and salts to feed plants | Makes use of natural waste conversion process resulting in better plant growth and lower disease rates. |
Photo Credits: Aquaponic Fun
Indeed, hydroponics and aquaponics share some distinct similarities. In terms of plant growth and productivity, both are known to yield better results than soil-based system. When comparing the two, however, there are quite a few significant differences where aquaponics ranks better. Apart from its natural-based structure, cost and risks surrounding aquaponics are definitely much lower than hydroponics. It is no wonder that many institutions and gardeners are adopting this method nowadays