iAVS is a sustainable method of growing plants and fish together in a closed-loop ecosystem.
The system consists of two main components: a fish tank and a grow bed.
The fish tank is where you keep your fish, such as tilapia or catfish. The fish produce waste that contains nutrients like nitrogen and phosphorus. This waste water is then pumped into the grow bed, which is filled with sand that acts as both a bio-filter and plant substrate.
As the water flows through the sand, it gets cleaned by beneficial bacteria that break down the waste into nutrients that can be absorbed by the plants.
The clean water then flows back into the fish tank, providing a continuous cycle of nutrient exchange between the plants and fish.
The plants grown in iAVS are typically vegetables like lettuce, tomatoes, or herbs. They thrive on the nutrient-rich water provided by the fish waste. In turn, they help to purify the water for the fish by removing excess nutrients.
One of the benefits of iAVS is its sustainability. It uses less water than traditional farming methods because it recirculates water within the system.
It also produces both fresh vegetables and protein-rich fish in one compact space.
To set up an iAVS system, you will need a few basic materials such as containers for your fish and grow bed, pipes to connect everything together, sand for your grow bed, and plants to grow.
The Integrated Aqua-Vegeculture System (iAVS) uses coarse sand as a growing media and bio-filter, which provides high yields while being water-efficient and environmentally friendly.
iAVs, or integrated Aqua-Vegeculture System, is a method of agriculture that was developed to address the challenges of food production in arid and underdeveloped regions like the African Sahel. It is a low-cost, low-tech system that combines aquaculture and horticulture in a closed-loop system, allowing for the production of fresh fish and vegetables in a small space. The goal of iAVs is to provide a sustainable source of food and nutrition for communities in need.
To successfully operate an iAVS system, one needs to have a basic understanding of horticulture and aquaculture. Knowledge of plant physiology, soil science, pest management, and water quality management is essential. Experience in managing hydroponics, fish tanks and growing plants is also helpful.
In terms of equipment, an iAVS system requires a fish tank or tanks, sand beds for growing plants, and a pump to circulate water between the fish tank and sand beds. The sand bed serves as both the mechanical filter and biological filter, eliminating the need for additional filtration equipment.
Aeration equipment may also be needed to maintain dissolved oxygen levels in the water. The time required to operate an iAVS system depends on several factors such as the size of the system, number of crops grown, and level of automation.
Generally speaking, an iAVS system requires regular monitoring and maintenance to ensure optimal plant growth and fish health. This includes monitoring water quality parameters such as pH, dissolved oxygen levels, and nutrient concentrations; managing pests and diseases; pruning plants; harvesting crops; and feeding fish.
Overall, operating an iAVS system requires knowledge of horticulture, aquaculture, and hydroponics; experience in managing fish tanks and growing plants; equipment such as fish tanks, sand beds, pumps; aeration equipment (if needed); regular monitoring and maintenance to ensure optimal plant growth and fish health.
Sand is used in iAVS systems because of its unique properties that make it an ideal growing medium and bio-filter.
The coarseness of the sand creates large pore spaces that allow for fast drainage and a vacuum effect, which replaces the oxygen around the roots of plants. This promotes healthy root growth and allows for efficient nutrient uptake. In addition, sand develops a biofilm over time that stores water and nutrients while providing food and homes for beneficial microbes.
This biofilm helps to maintain a healthy balance of microorganisms in the system, which is essential for optimal plant growth and water filtration.
Sand has been used for centuries as a water filtration device due to its ability to remove impurities from water. The ancient Egyptians were known to use sand filters to purify their drinking water, and sand filtration has been used in municipal water treatment plants since the early 1800s.
Today, sand remains one of the most effective and widely used filter media due to its low cost, durability, and effectiveness at removing contaminants from water. In iAVS systems, sand serves as both a growing medium for plants and a bio-filter for fish waste. It provides an efficient way to recycle water within the system while promoting healthy plant growth and maintaining clean water for fish.
Overall, sand is an essential component of iAVS systems due to its unique properties that promote healthy plant growth, support beneficial microorganisms, and provide effective water filtration. Its long history of use in water treatment further underscores its effectiveness as a filter media.
The iAVS Research Team from 1984 to 1994 was a large and diverse group of researchers and consultants from various institutions and disciplines, including agriculture, horticulture, and engineering. The team collaborated with many external institutions and received recognition for their work, with 10 members being honored as “Fellows” of their respective professional discipline. Their research has been cited in numerous journal articles and has been tested and proven.
iAVs is a research project that aims to develop sustainable and efficient methods for growing food using aquaponics and sand-based systems. The project is open-source, meaning that the research and findings are available to everyone and can be replicated or improved upon by anyone interested in the field. There is no business structure or ownership associated with the project, and the researchers encourage others to contribute to the advancement of the research.
The open-source nature of iAVS is a key part of its history. The system was developed in the 1980s by Dr. Mark McMurtry, with the assistance of many collaborators. From the beginning, Dr. McMurtry envisioned iAVS as a system that could be used by people all over the world to grow food sustainably. To achieve this goal, Dr. McMurtry made the decision to make iAVS an open-source system. He believed that this would allow people to adapt the system to their local conditions and needs, and would encourage innovation and collaboration among users.
Today, there is a vibrant community of iAVS users around the world who are working together to refine and improve the system. They share information about their experiences with different crops, fish species, water quality management techniques, pest control methods, and other aspects of operating an iAVS system.
Open-source systems like iAVS are designed to be accessible and adaptable. They are developed with the goal of sharing knowledge and empowering people to solve problems in their own communities. This is in contrast to closed systems that are often developed by companies or individuals who seek to profit from their technology.
The Speraneo system, for example, is a proprietary aquaponics system that was developed by a company called Speraneo Aquaponics. The company claims that its system is superior to other aquaponics systems because it uses a patented design that maximizes fish production. However, because the system is proprietary, it is not accessible to everyone, and its cost may be prohibitive for many people.
Similarly, the UVI research on aquaponics was conducted by researchers at the University of the Virgin Islands with funding from private companies. While this research has contributed valuable knowledge about aquaponics, some critics have argued that it has been influenced by corporate interests and has not always been transparent about its methods or results.
In contrast, iAVS is an open-source system that was developed with the goal of sharing knowledge and empowering people around the world to grow food sustainably. Its plans and instructions are freely available online, and users are encouraged to modify and adapt the system as needed for their local conditions.
An iAVS system is a closed-loop system that uses sand as a growing medium and bio-filter.
The system consists of a fish tank, a grow bed filled with sand, and a pump that circulates water between the two.
During each irrigation cycle, water is pumped from the fish tank up to the grow bed. The water is distributed evenly across the surface of the sand in furrows between raised ridges.
These ridges help to concentrate detritus into narrower channels where it can build up along the bottom faster and help water move laterally more uniformly. By doing so, there is less chance to block surface pore spaces over a greater area which leaves more area (pores) available for atmosphere (oxygen) to enter easily into the root zone and microbes below the surface.
As water percolates down through the sand in each furrow, it gets cleaned by beneficial bacteria that break down fish waste into nutrients that can be absorbed by plants. The clean water drains back to the fish tank via a drain pipe.
It's important to note that during each irrigation cycle, it's recommended to water until saturation. This means watering until all of the sand in each furrow is fully saturated with water before draining back to the fish tank. This ensures that plants receive enough water and nutrients for optimal growth.
The length and frequency of irrigation cycles will depend on factors such as plant growth stage, temperature, humidity, and other environmental conditions. In general, shorter cycles with more frequent watering are better for young plants with shallow roots while longer cycles with less frequent watering are better for mature plants with deeper roots.
Efficient drainage and high oxygen levels in an iAVS system benefit the microbes and rhizosphere in several ways.
Firstly, obligate aerobes require oxygen for cellular respiration to oxidize substrates such as amino and nucleic acids, ammoniacal-N, lipids, etc. to obtain energy. Therefore, increased oxygen concentration due to efficient drainage and high oxygen levels in the soil atmosphere promotes the growth of these beneficial microbes.
Secondly, forced cellular (membrane) physical contact with oxygen due to individually smaller yet greater composite surface area contact and more uniformly distributed pore volumes provides a far greater colonized surface area in direct contact with oxygen. This means that more microbes can grow and thrive in the soil environment.
Thirdly, temporal retention of and direct microbial contact/interaction with plant root exudate contributes to a more diverse and effective soil ecology. This means that the beneficial microbes are able to interact with plant roots more effectively, leading to better nutrient uptake by plants.
These benefits to the microbes and rhizosphere also benefit water filtration by promoting the growth of beneficial bacteria that break down fish waste into nutrients that can be absorbed by plants.
The recommended irrigation schedule for an iAVS system is to repeat the filtration/irrigation event at regular intervals during daylight hours for as many as eight times per day.
The principle operational criterion is to incrementally and cumulatively circulate the equivalent of twice the total fish tank volume (at a minimum) through the filter bed every day. This ensures that plants receive enough water and nutrients for optimal growth while also maintaining clean water for fish in the system.
However, it's important to note that the length and frequency of irrigation cycles may need to be adjusted based on factors such as plant growth stage, temperature, humidity, and other environmental conditions.
Overall, an iAVS system operates by recirculating nutrient-rich water between a fish tank and a grow bed filled with sand. This closed-loop system promotes healthy plant growth while providing clean water for fish in an environmentally sustainable way. The use of furrows and ridges, watering until saturation, and monitoring drainage times are all important factors in ensuring optimal plant growth and system performance.
The result is a sustainable and organic system that produces high yields of both fish and plants while using minimal water and no harmful chemicals or pesticides. With proper management of sand quality and nutrient levels, iAVS can be an efficient way to grow food in any climate or location.
iAVS offers several benefits over traditional aquaponics and hydroponics systems. Here are some of the key advantages:
- High yields: iAVS can produce up to 10 times more food per unit area than traditional soil-based agriculture, making it an efficient way to grow food in urban or limited-space environments.
- Water efficiency: iAVS uses minimal water compared to traditional agriculture, with the only water lost through evaporation and transpiration. This makes it ideal for areas with limited water resources or drought-prone regions.
- Organic and sustainable: iAVS is a completely organic and sustainable method of growing food, with no need for harmful chemicals or pesticides. It also reduces waste by using fish waste as a nutrient source for plants.
- Climate resilience: iAVS can be adapted to different climates and locations, making it a versatile method of food production that can withstand extreme temperatures and weather conditions.
- Community building: iAVS is often practiced in community settings, which fosters collaboration and knowledge-sharing among growers. This creates a sense of community ownership over the food production process and promotes social cohesion.
Overall, iAVS is a promising method of sustainable food production that offers numerous benefits over traditional agriculture. With proper management and care, it has the potential to revolutionize the way we grow food in the future.
The iAVS system has several unique features that set it apart from other forms of aquaculture and agriculture.
One of the most notable features is the use of sand as a filter for fish waste.
The sand is shaped into channels (furrows) and the water runs down them, evenly distributing the fish waste (solids) and forming a biofilm to convert the nutrients (mineralize) into plant-available forms for the plants that sit in the raised ridges (crowns).
Another unique feature of iAVS is its ability to be built in places with no electricity or plumbing, making it accessible to people living in remote areas. It also uses local materials and unsophisticated managerial skills, which means that it can be operated by people with little to no technical expertise.
The iAVS system maximizes water conservation by recycling water through the system multiple times. The waste-laden water is passed through a physical filter (the sand bed), which also acts as a ‘living filter’ (the vegetable crops and micro-flora resident in the sand bed), and finally across an aerating cascade (or other aeration device) as it is returned to the fish-culture tank.
Overall, these unique features make iAVS an attractive option for sustainable agriculture in underdeveloped regions where resources are limited. By using sand as a filter, maximizing water conservation, and requiring minimal technical expertise, iAVS provides an efficient and accessible method for producing nutritious food while minimizing waste.