FarmHub
Operating an aquaponic system
Basic system maintenance and operation procedures To ensure that the aquaponic system is running well one should prepare clear operating, maintenance and troubleshooting instructions (manuals), and also checklists of daily, weekly and monthly activities for which records should be kept. This way, different staff members will always know what to do. All observations and tasks performed need to be entered (with specific dates) in a dedicated record book, that must be stored in a visible place.
· Aqu@teachNutrient supply in aquaponics
The chemical composition of system water in aquaponics is very complex. Besides a large array of dissolved ions, it contains organic substances resulting from the release of products of fish metabolism and feed digestion, as well as substances excreted by the plants. These substances are largely unknown, and their interactions can further influence the chemical composition and pH of aquaponic nutrient solutions. All this can exert manifold, but mostly yet unknown, effects on the nutrient uptake by plants, on fish health, and on microbial activity.
· Aqu@teachManagement of recirculating aquaculture system (RAS)
Stocking density Stocking density is a very important factor that has to be decided in advance when designing a RAS. Stocking density can be defined in different ways (Table 2), and it is important to be aware when and why different definitions are being used. Table 2: Stocking density definitions Density of individuals Biomass density per surface (#/m2) per volume (#/m3) per surface (kg/m2) per volume (kg/m3) Independent of tank depth.
· Aqu@teachMain interactions between ingestion and environmental factors
As commented above, we should be able to house each species according to its requirements. For that we first need a profound knowledge of the species that we are going to work with before we begin to grow the fish or start the installation. Once we have this information, we should be able to maintain the adequate housing conditions in our system, which in this case is related to aquaponic systems.
· Aqu@teachMacro- and micronutrients
The elements of the universe There are 92 naturally occurring elements on the Earth. Some are very well studied, some not at all: for example astatine (Bryson 2003). The problem is that some elements are very rare. For example, only 24.5 grams of francium occur at any time in the whole of the Earth’s crust. Only about 30 of the naturally occurring elements are widespread on Earth, and very few are important for life (Figure 1).
· Aqu@teachLiving walls
Living walls are often used in architecture to provide aesthetic, ecological and environmental benefits in urban areas. The modular panels, comprised of polypropylene plastic containers or geotextile mats, support plants which provide benefits not only in visual terms, but also with regards to amenity, biodiversity, thermal efficiency and amelioration of air pollutants, all for a very small ground level footprint (Manso & Castro-Gomes 2015; Perini et al. 2013). Two universities have been investigating the potential for living walls for growing edible crops using aquaponics.
· Aqu@teachLegislation and governance
A range of factors – existing urban layout, perceptions and attitudes towards the use of urban space, and the prevalent political climate – all operate at the city-specific level to influence the development of urban agriculture. In most countries in the Global North there is no independent category for urban agriculture in municipal zoning plans, as agriculture has historically been regarded as a rural activity by urban planners. Urban agriculture in Europe appears to fall between different policy areas, despite assurances from the European Commission that Member State rural development programmes can be used for the benefit of urban agriculture.
· Aqu@teachLegal framework
The goal of the food safety policy of the EU is to ensure safe and nutritious food from healthy animals and plants while supporting the food industry (EC 2014). The integrated Food Safety policy also includes animal welfare and plant health. In the strategy for animal welfare there is an action on the welfare of farmed fish, though there are no specific rules in place (EC 2012). Because of the great variety of potential produce, food safety norms are not explicit for aquaponic produce and there are no specific EU regulations yet (Joly et al.
· Aqu@teachIntroduction to urban agriculture
Urban agriculture takes many forms. These can range from household, school and community gardens to rooftop and indoor farms. A fundamental distinction is often made between urban agriculture (involving food production in an urban area) and peri-urban agriculture, which occurs on the fringes of cities. In the case of the latter, farming is largely undertaken by professional farmers on land that has often already been used for farming for decades. An urban farm is a part of a local food system where food is cultivated and produced within an urban area, and marketed to consumers predominantly within that urban area.
· Aqu@teachIntroduction to monitoring
Scientific parameters A scientific parameter is a definable or measurable characteristic or a value, selected from a set of data. A variable is any factor, trait, or condition that can exist in differing amounts or types. In experimental science, there are usually three types of variables: 1) independent, 2) dependent, and 3) controlled. The independent variable is the one that the experimenter changes in order to measure or observe a response or an effect.
· Aqu@teach