AQUAPONICS VERSUS HYDROPONICS
Is Aquaponics commercially viable?
Aquaponics is becoming the spoken word in agriculture today. It is becoming a commercial enterprise for many. My advice to you is to make sure that the person giving you advice and selling you a system is not the only one making a huge profit.
Aquaponics can be profitable if all factors are considered in the design of your system. Maintaining optimum water temperature is key. The efficient growth of plants is having optimum root zone temperature throughout the year. Heating water is expensive so when deciding on Aquaponics as an option make sure you do proper research about the climate in your area and what is going to be required to keep water temperature within optimum ranges for both plant and fish.
Aquaponics has many advantages when setup correctly. (Buy wisely) Aquaponics can have high set up costs, so buy well. Through my experience I will show you options so as to eliminate some of those costs. Once you get over the setup costs the running costs are much lower including the labour input.
Aquaponics is not very complicated and if I can do it with no prior agricultural training many of you can also do it. Nature wants to survive and aquaponics being a complete ecosystem is forgiving if the system is correctly designed and you follow the guidelines given. That is why before you start this journey it is important to attend a course and understand the fundamental principles of aquaponics. From the general observation you would think it is all about the plants and fish but it’s more about the invisible, namely the bacteria that keeps the ecosystem healthy that everything else can survive. We will be focusing a lot on the invisible heroes.
If you are like me and love farming it is important to know that the farming part is the easy part and the part that needs even more attention is the marketing part. To ignore this part is failure.
Have a plan!
A business plan is vital to your success. Study the market you are entering first. The vegetable market is a competitive market. Know the role players and the competition. Know what they supply and for how much. Speak to potential buyers and understand their buying policies. Many retailers support small scale farmers, others don’t have the time and order directly from a distribution centre. Know the demand, decide on a product, do the calculations and get the agreement. Do not invest in this game if you do not have a clear plan.
Once you have your overall plan, make sure you plan daily and weekly. Planning is everything. Staying ahead is survival. Knowing your seasons and planting schedules to make sure you have available what is in demand for that season. There are many reasons to have good planning. Stay on top of things.
Before starting up, know your seasons and temperature of your local area to know what plants and what fish will thrive in your system.
Tilapia is the most common species for aquaponics. There are various types we will cover further on in the training but is important to know what species is best. Considering that some species do not thrive or even survive in temperatures below 15˚C, and some are alien invasive to your area and need special permits and approvals. Then there are trout, bluegills and catfish. If you want to go decorative you can go koi or goldfish. Know what temperatures the fish can survive at and know the legislation applicable to your area. Also know rate of growth if you are interested in farming them for food.
What type of plants?
The plants you can grow in aquaponics is quite broad. Considerations would be temperatures and pH levels. Aquaponics runs effectively with a ph between 6.5 and 7. Rooting crops, like carrots and potatoes would work well in a wicking bed.
Advantages and disadvantages of aquaponics.
Aquaponics has several advantages over other recirculating aquaculture systems and hydroponic systems that use inorganic nutrient solutions. The hydroponic component serves as a biofilter, and therefore a separate biofilter is not needed as in other recirculating systems. The biofilter, in our case the media beds or gravel beds provides the location for bacteria to convert ammonia, which is toxic for fish, into nitrate, a more accessible nutrient for plants.
Aquaponic systems have the only biofilter that generates income, which is obtained from the sale of produce such as vegetables, herbs and flowers.
Aquaponics increases profit potential due to free nutrients for plants, lower water requirements, elimination of a separate biofilter, less water quality monitoring and shared costs for operation and infrastructure.
The concept is very simple, requiring no special skills or formal educational qualifications. Aquaponics provides year-round, fresh nutritious fish and organic vegetables. The system is recirculating and uses very little make-up water. Water is only lost to evaporation and plant uptake. The system can be situated on land that is no good for traditional agricultural crop production with limited water supplies. Absolutely NO chemicals or fertilizers are required or used with this system.
ADVANTAGES
REDUCED LAND AREA REQUIREMENTS
REDUCED WATER CONSUMPTION
ACCELERATED PLANT GROWTH RATES
YEAR-ROUND PRODUCTION IN CONTROLLED ENVIRONMENT
MULTIPLE CROPS PRODUCED SIMULTANEOUSLY
OPERATIONAL EFFICIENCY WITH SHARED EQUIPMENT
LOW RUNNING COSTS
DISADVANTAGES
HIGH START-UP COSTS
NEEDS RELIABLE ELECTRICITY
MANAGING WATER TEMPERATURE CAN BE EXPENSIVE
Aquaponic systems offer several advantages. In recirculating aquaculture systems, the disposal of accumulated waste is always a major concern. Recirculating systems are promoted as a means of reducing the volume of waste discharged to the environment. Certainly, the volume is reduced, but the pollution load (organic matter, dissolved nutrients) per unit of discharge is correspondingly higher. This more concentrated discharge may pose a threat to the environment in some situations, or an additional expense if the wastewater is discharged to a municipal system for further treatment.
In aquaponic systems, plants recover a substantial percentage of dissolved nutrients, thereby reducing the need to discharge water to the environment and therefore extending water use i.e. by removing dissolved nutrients through plant uptake, the water exchange rate can be reduced. Minimizing water exchange reduces operating costs of aquaponic systems in arid climates and heated greenhouses where water or heated water represents a significant expense.
Profitability is a major concern when considering the use of a recirculating system. Recirculating systems are expensive to construct and operate, and profitability often depends on serving niche markets. By incorporating aquaponics, a secondary plant crop, which receives most of its required nutrients at no additional cost, improves system profit potential. The daily feeding of fish provides a steady supply of nutrients to plants which reduces or eliminates the need to discharge and replace depleted nutrient solutions or adjust nutrient solutions as is required in hydroponics. The carbon dioxide vented from fish culture water can increase plant yields in tightly enclosed greenhouses during the winter growing season. The plants purify the culture water and can, in a properly sized and designed facility, eliminate the need for separate and expensive biofilters. In aquaponic systems employing gravel or raft hydroponics, the hydroponic component can provide sufficient biofiltration for the fish and therefore the cost of purchasing and operating a separate biofilter is avoided.
These costs are charged to the hydroponic subsystem which generates substantial income if there is a good market for the vegetable crop. The expense of water quality monitoring is reduced in aquaponic systems as waste nutrients are generated daily and there is generally excess wastewater treatment capacity. An aquaponics system also generates savings in several areas of construction and operation by sharing operational and infrastructure costs for system maintenance, pumps, blowers, reservoirs, heaters and alarm systems. Initial capital investment is reduced in that an aquaponic system can be erected with a modest increase in acreage over that required for a hydroponic system. Aquaponic systems do require high capital investment, moderate energy inputs and skilled management. The premium prices available in niche markets may be required for an aquaponic system to be profitable.
There are of course disadvantages to aquaponic systems. The most obvious of these is the large ratio of plant growing area in comparison to the fish rearing surface area. A large ratio of plant to fish surface area is needed to achieve a balanced system where nutrient levels stay relatively constant. Ratios vary from 2:1 to 10:1 or greater depending on the degree of solids removal with larger ratios needed as solids removal efficiency decreases. In essence, aquaponic systems emphasize plant culture, which is an advantage if viewed by a horticulturist. Most of the labour in the facility is devoted to seeding, transplanting, maintaining, harvesting and packing plants. Additionally, a new set of skills is required for the plant component; so a commercial operation would do better with both an aqua culturist and a horticulturist on staff. Another disadvantage is that the horticulturist must rely on biological control methods rather than pesticides to protect the plants from pests and diseases. However, this restriction can be viewed as an advantage in that the plant products can be niche marketed as “pesticide free”.
