Problems & Solutions

The are several major problems with our food system as shown by all of the statistics. The need for change is exacerbated by the growth of urban populations and environmental concerns coming to bear over the next decades. Aquaponics, hydroponics, and aquaculture seem to be a key part of our solutions to these problems. But, aquaculture and hydroponics each have significant environmental downsides that aquaponics does not. The trends point to growth in all three industries, but with aquaponics gaining a much larger share of the pie.

  • Urban Food Access
  • Efficient Growing
  • Overfishing and the Need for Protein
  • Pesticides, Fertilizers, and Antibiotics
  • Local Society and Economy
  • Why is Aquaponics Better than Hydroponics and Aquaculture?

Urban Food Access
Continuing population growth and urbanization are projected to add 2.5 billion people to the world’s urban population by 2050. (United Nations)

“One in seven District [of Columbia] households is struggling against hunger, and while the nation’s federal nutrition programs have a wide reach in Washington, D.C., too many adults and children continue to slip through the nutrition safety net. The ability to obtain enough food for an active, healthy life is the most basic of human needs. Without access to adequate healthy food, people are likely to be hungry, undernourished, and in poor health, with high rates of obesity, heart disease, diabetes, and other nutrition-fueled health problems.” (dchunger.org)

The USDA reported that in 2014, 14% of U.S. households were food insecure at least some time during the year, including 5.6 percent with very low food security, meaning that the food intake of one or more household members was reduced and their eating patterns were disrupted at times during the year because the household lacked money and other resources for food. (Coleman-Jensen et al, 2015)

“Everybody, regardless of their economic means, should have access to the same healthy, safe, affordable food that is grown naturally.” (Will Allen, Growing Power)

“Eighty percent of the US population and over 50% of the world’s population now live in urban areas. Food security therefore cannot be addressed without solutions that reimagine the food system as decentralized and urban. Such a distributed urban food system can offer better nutritional value and be more energy efficient and resilient.” (O’Hara, 2015)

Eleven percent of greenhouse gas emissions associated with the US food supply chain are transportation related. (USDA)

In the past 15 years the nutritional content of food has decreased 25%. (USDA)

Aquaponic systems can be set up almost everywhere and have the potential to (sub-)urbanize food production. This could bring important socio-environmental benefits. Aquaponic farming plants could be implemented in old industrial neglected buildings with the advantages of re-establishing a sustainable activity without increasing urbanization pressure on land. Roof gardens would be another possibility, allowing the saving of space in urban areas. If greenhouses are used on roofs, they can insulate buildings while producing food. Another important aspect is minimizing the distance between the food producer and consumer. The longer the supply chain, the more transport, packaging, conservation and labor needed, leading to substantial decreases of resources and energy (e.g., up to 79% of the retail price in US conventional food distribution). Shortening and simplifying the food supply chains can drastically diminish their environmental impacts, while providing cities with fresher products. This also allows the consumer to clearly identify his food origin. Nevertheless, one should not underestimate the development of rural locations, where farmland is plentiful. As aquaponics can be considered a high-tech agricultural method, it is necessary to assure knowledge transfer in this field to maintain skilled labour forces. (Goddek et al, 2015)

Efficient Growing
Agriculture is a major user of ground and surface water in the United States, accounting for approximately 80 percent of the Nation’s consumptive water use and over 90 percent in many Western States. (USDA)

According to state water managers, experts, and literature GAO reviewed, freshwater shortages are expected to continue into the future. In particular, 40 of 50 state water managers expected shortages in some portion of their states under average conditions in the next 10 years. (GAO)

Aquaponics uses less than 10% of water compared to conventional agriculture, depending on the climatic conditions. Aquaponics can grow in locations with drought, poor soil quality, or challenging climates. (Goddek et al, 2015)

Aquaponics is most appropriate where land is expensive, water is scarce, and soil is poor. Deserts and arid areas, sandy islands and urban gardens are the locations most appropriate for aquaponics because it uses an absolute minimum of water. There is no need for soil, and aquaponics avoids the issues associated with soil compaction, salinization, pollution, disease and tiredness. Similarly, aquaponics can be used in urban and peri-urban environments where no or very little land is available, providing a means to grow dense crops on small balconies, patios, indoors or on rooftops. (Somerville et al, 2014)

The most intensive hydroponic culture can achieve 20–25 percent higher yields than the most intensive soilbased culture… This is when hydroponic culture uses exhaustive greenhouse management, including expensive inputs to sterilize and fertilize the plants. Even without the expensive inputs, the aquaponic techniques described in this publication can equal hydroponic yields and be more productive than soil. (Somerville et al, 2014)

In a 2004 study, “Update on Tilapia and Vegetable Production in the UVI Aquaponic System” aquaponic pioneer James Rakocy and other researchers compared the yields of a leafy herb (basil) and a fruiting vegetable (okra) grown in aquaponic vs. field production systems. Basil and okra were raised in deep water culture systems. Yields of aquaponic basil were three times greater than field-grown, while yields of aquaponic okra were 18 times greater than field-grown. (Rakocy et al, 2004)

Overfishing and the Need for Protein
Fish is one of the most efficient animal protein producers, with a food conversion ratio between 1 and 2. Since fish demand is increasing whilst the fishing grounds are overexploited, aquaculture is the fastest growing sector of world food production. However aquaculture, alone, has significant negatives. (Goddek et al, 2015)

Eighty percent of the world’s oceans are fully- or over-exploited, depleted or in a state of collapse. One hundred million tons of fish are consumed worldwide each year, providing 2.5 billion people with at least 20% of their average per capita animal protein intake. (Somerville et al, 2014)

Aquaculture has helped improve nutrition and food security in many parts of the world. Increasing global population coupled with increased per capita seafood consumption result in constant, growing demand for seafood. Global seafood consumption reached 143 million metric tons in 2009, which is an increase of more than 20 million tons in 10 years. According to the United Nations Food & Agriculture Organization, “With capture fisheries production stagnating, major increases in fish food production are forecast to come from aquaculture. Taking into account the population forecast, an additional 27 million tonnes of production will be needed to maintain the present level of per capita consumption in 2030.” Aquaculture is one of the most resource-efficient ways to produce protein. (NOAA)

Of the total amount of seafood consumed in the United States,over 91% (by value) is imported from foreign countries– about half of that is produced by aquaculture. (NOAA)

In 2011, the U.S. trade deficit in seafood was $11.2 billion. That number grows annually and is second only to oil. (NOAA)

Two decades ago, Viet Nam had only traditional aquaculture for local consumption. Today, Viet Nam is the largest exporter of aquaculture products, reaching customers all over the globe. Growth in aquaculture has been nothing short of remarkable over the past two decades, transforming from a niche and experimental form of production to market dominance. (OECD, 2014)

Pesticides, Fertilizers, and Antibiotics
No matter what methods are used, agriculture always has some impact on the environment. But industrial agriculture is a special case: it damages the soil, water, and even the climate on an unprecedented scale. Intensive monoculture depletes soil and leaves it vulnerable to erosion. Chemical fertilizer runoff and CAFO wastes add to global warming emissions and create oxygen-deprived “dead zones” at the mouths of major waterways. Herbicides and insecticides harm wildlife and can pose human health risks as well. Biodiversity in and near monoculture fields takes a hit, as populations of birds and beneficial insects decline. (Union of Concerned Scientists)

Overuse of antibiotics in meat production (in the U.S., more antibiotics are consumed each year by healthy animals than by sick humans) has contributed to a growing problem of antibiotic resistance that is having a serious impact on the treatment of infectious diseases. And a similar over-reliance on the herbicide glyphosate (marketed by Monsanto Co. as Roundup) has spawned a burgeoning population of Roundup-resistant “superweeds” that has become a scourge for farmers in many areas of the U.S., especially the South and Midwest. (Union of Concerned Scientists)

There is growing interest in aquaponics because it can be practiced in non-traditional locations for agriculture such as inside warehouses and on marginal lands, and it can provide locally grown products without using synthetic pesticides, chemical fertilizers, or antibiotics. (Love et al, 2015)

In terms of sustainability, both phosphorus and potassium are major components of agricultural fertilizers, and like oil, they are non-renewable resources. Therefore, increasing use and depletion of these minerals without reuse or recapture has a negative impact on and is of significance to their future supply. This in turn would have dramatic consequences for global food security. Nutrient recycling policies, especially for phosphorus, are crucial in order to avoid global food shortages. (Goddek et al, 2015)

Local Society and Economy
Socially, aquaponics can offer quality-of-life improvements because the food is grown locally and culturally appropriate crops can be grown. At the same time, aquaponics can integrate livelihood strategies to secure food and small incomes for landless and poor households. Domestic production of food, access to markets and the acquisition of skills are invaluable tools for securing the empowerment and emancipation of women in developing countries, and aquaponics can provide the foundation for fair and sustainable socio-economic growth. Fish protein is a valuable addition to the dietary needs of many people, as protein is often lacking in small-scale gardening. (Somerville et al, 2014)

UDC’s planned Washington DC urban food hubs will incorporate aquaponics and hydroponics. The hubs are intended to “create a network of skills, jobs, and business ownership that broadens local food production.” (O’Hara 2015)

“Farming is no longer about how to use a shovel and a rake, it’s about how to run a robot, and work the Web. You need a level of technology now to grow food. Aquaponics is a good marriage of the old and the new. We need those jobs to be filled and we want people to be interested.” (Sundown Hazen on PBS Newshour)

A small-scale aquaponic system [about a 300 gallon fish tank] cannot provide all the food a family requires, but it can provide a healthy source of food, promote family independence, provide a fun hobby for adults and children, and possibly provide a small income through the sale of fish and produce. Operating a small-scale aquaponic system can be rewarding and educational for a family producer. (Engle, 2015)

Why is Aquaponics Better Than Hydroponics and Aquaculture?
One of the main benefits of aquaponics is its ability to produce fresh vegetables and protein in a dense urban environment….. but so can aquaculture and hydroponics. So, why not run two separate simple aquaculture and hydroponic systems rather than constructing a complicated, recirculating aquaponic system? Because both aquaculture and hydroponics have significant downsides.

One major problem for the sustainability of aquaculture is the treatment of nutrient-rich wastewater, which is a by-product of all the aquaculture methods mentioned above. Depending on the environmental regulations set by each country, farmers must either treat or dispose of the effluent, which can be both expensive and environmentally harmful. Without treatment, the release of nutrient-rich water can lead to eutrophication and hypoxia in the watershed and localized coastal areas, as well as macroalgae overgrowth of coral reefs and other ecological and economical disturbances. (Somerville et al, 2014)

Aquaculture activities interact with the surrounding environment. As aquaculture continues to intensify and expand, discharges of organic wastes, nitrogen and phosphorous may result in local environmental degradation. This is a main source of criticism of aquaculture and explains why strict restrictions on aquaculture expansion are in place in many countries. The use of antibiotics has also been a concern because of the potential harm to humans and the environment when dissipated into the surrounding water and taken up by other aquatic species. (OECD, 2014)

High yield hydroponic systems require a considerable amount of macro- and micronutrients from industrial and mining origin, leading to high energy (i.e., for production and transport) and finite resources use (e.g., phosphorus and oil). (Goddek et al, 2014)

Conventional hydroponics requires mineral fertilizers in order to supply the plants with necessary nutrients but the aquaponics systems use the available fish water that is rich in fish waste as nutrients for plant growth. Another advantage of this combination lies in the fact that excess of nutrients does not need to be removed through periodical exchange of enriched fish water with fresh water as practiced in aquaculture systems. The system results in a symbiosis between fish, microorganisms and plants, and encourages sustainable use of water and nutrients, including their recycling. Within this synergistic interaction, the respective ecological weaknesses of aquaculture and hydroponics are converted into strengths. This combination substantially minimizes the need for input of nutrients and output of waste, unlike when run as separate systems. (Goddek et al, 2015)

Six crops (cucumber, tomato, basil, rosemary, Echinacea and lettuce) were grown in aquaponics and hydroponics nutrient solutions in model greenhouse experiments using raft hydroponics. Aquaponically produced plants attained a higher relative growth rate for both roots and shoots compared to plants grown hydroponically under non-limiting nutrient conditions. (Savidov, 2005)