Integrated aquaculture-agriculture: Fish culture and plant crops module for arid areas Farmers guide In partnership with Photo credit: Ahmed Elewa/WorldFish Integrated aquaculture-agriculture: Fish culture and plant crops module for arid areas Authors Ahmed Elewa and Ahmed Nasr-Allah. Citation This publication should be cited as: Elewa A and Nasr-Allah A. 2023. Integrated aquaculture-agriculture: Fish culture and plant crops module for arid areas. Penang, Malaysia: WorldFish. Guidelines: 2023-11. Acknowledgments This work was undertaken as part of the Advancing Climate Smart Aquaculture Technologies (ACliSAT) project, funded by the International Fund for Agricultural Development (IFAD). WorldFish recognizes those who have participated in earlier workshops and events under two other projects: Sustainable Transformation of Egypt’s Aquaculture Market System (STREAMS) and Fragility to Resilience in Central and West Asia and North Africa (F2R-CWANA). Special thanks to Dr. Osama Kadour, Dr. Ahmed Zaher, Dr. Salah Hagag, Dr. Mohamed Elgazar and Dr. Samir Ahmed Ali. Contact WorldFish Communications and Marketing Department, Jalan Batu Maung, Batu Maung, 11960 Bayan Lepas, Penang, Malaysia. Email: worldfishcenter@cgiar.org Creative Commons License Content in this publication is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License (CC BY-NC 4.0), which permits non-commercial use, including reproduction, adaptation and distribution of the publication provided the original work is properly cited. © 2023 WorldFish. Photo credits Front cover, page 9, Ahmed Elewa/WorldFish; pages 18, 19, Ahmed Nasr-Allah/WorldFish; pages 8, 10, Ibrahim Elsira/WorldFish; pages 13, 15, WorldFish. i Table of contents Introduction 1 1. Agricultural land 2 2. Optimal crop composition 3 3. Water requirements for plants 4 4. Agriculture and aquaculture in arid areas 5 5. Irrigation strategies and considerations 6 6. Designing a fish culture unit 8 7. Fish culture 11 8. Fish nutrition 12 9. Water management in fishponds 14 10. Fish health 16 11. Fish harvesting and post-harvest procedures 17 12. Marketing 19 13. Social responsibility 20 Notes 21 References 21 Appendix 1. Water requirements for crops in Egypt 22 ii Introduction This guide explains the integration between fish culture and conventional crop agriculture and discusses how farmers can maximize benefits from using these resources.1 The main concept for any system of integration is that the outputs of one organism or system function as a source of inputs for another organism or system. For fish farmers, this concept applies to the relationship between fish and crops, as the outputs of the fish can be a rich source of nutrients for crops. An integrated aquaculture-agriculture system has the following advantages: • Taking water used for fish farming and reusing it to irrigate crops optimizes water use. • Aquaculture-agriculture integration is environmentally friendly, as crops benefit from the nutrients in the water. This minimizes the amount of additional fertilizers and thus cost. Using nutrients discharged from fish culture units also helps reduce environmental impact. • Producing fish in remote and rural areas, away from traditional fish farming and fishing sites, reduces transportation costs and provides fresh fish for consumers. • A small-scale farm can use this system for either home or local consumption, or both, as it is possible to produce more than one agricultural product in a relatively remote areas where getting fresh animal food may not be available. • It is possible to produce organic food products that have a higher market value compared to traditional crops as fish generate organic fertilizer waste to that can be used in crop fertilization. This guide focuses on integration between fish and crops. However, farmers can introduce several other models, including livestock and poultry, in proportion to their integrated system to maximize benefits from all outputs and to increase profitability (Figure 1). When designing an integrated aquaculture-agriculture farm, it is important to consider the water requirements for growing crops, the volume of the fish culture unit and the targeted fish production. Water source Tilapia culture tank Revenue Catfish culture tan k Revenue Animal production Revenue (meat, milk, wool, etc.) Agriculture cro ps Organic fertilizers Revenue Revenue Figure 1. An integrated system between different types of agricultural activities. 1 1. Agricultural land Agricultural activity depends on the land and and associated foraging crops, as needed. This water characteristics as well as the supply and will diversify their income sources and maximize demand for various crops. This affects the choice returns on agricultural activity. For newly reclaimed of crop composition from one farm to another. sandy lands, it is best to focus on economical agricultural crops. Water requirements for land vary according to the crops grown. In an integrated aquaculture- In areas where water availability is uncertain, agriculture system, farmers first need to determine farmers must build reservoirs for irrigation. This how much water their crops require daily. Based is important in places that depend on distant on this, they can then go ahead and design their water sources or pumped groundwater, or fish farming system accordingly. when the water recedes at times. A reservoir provides farmers with sustainable irrigation For large crops, farmers can diversify their crops to for their crops. It is possible to establish and maximize their use of resources. Usually, they can exploit these reservoirs in harmony with fish add an animal production component to the farm farming in order to maximize the benefits and by allocating part of the land for animal husbandry other advantages, as listed in this section. 2 2. Optimal crop composition In integrated aquaculture-agriculture systems, the intercropping is a method in which fruit crops are types of crops farmers can cultivate depend on grown with vegetables and field crops. Table 1 the location and the surrounding environment, lists crops that are suitable for integrated farming in addition to fish production. For example, systems in Egypt. Field crops Vegetables Fruits Wheat Tomatoes Mangoes Sugar beetroots Potatoes Olives Forage beetroots Cucumbers Oranges Clover (alfalfa) Tangerines Yellow corn Eggplants Pomegranates Broad beans Peppers Palm trees Feed beans Table 1. The most suitable crops for aquaculture-agriculture integration in Egypt. In irrigation water, the salinity concentration olives and pomegranates, can tolerate high levels. affects the quality of crops that can be cultivated. Table 2 shows the relationship between the total Some crops, such as mangoes and vegetables, are salt concentration in water and its suitability for sensitive to salinity in water, while other crops, like irrigation purposes. Total salt concentration (ppm) Suitability for irrigation <160 This is suitable for irrigating all crops in every type of land. 160–500 This is suitable for irrigating low saline sensitive crops. 500–1000 This is suitable for irrigating low saline sensitive crops, provided the cultivated land has a good drainage system and allows enough water to wash away any salt residue in the roots. 1000–1500 This is suitable for irrigating well-drained sandy land, if the amount of water used is increased each time and farmers choose crops that can tolerate the salinity ratio. >1500 This water is not good for irrigation, especially drip irrigation. However, it can be used after mixing it with fresh water to reduce its salinity. The drip-spills localized irrigation systems can be used up to 7000 ppm. Table 2. Salt concentration in water and its suitability for irrigation. 3 3. Water requirements for plants Water requirements for agricultural crops vary As the water requirements for different agricultural depending on the following factors: crops vary, farmers can refer to the characteristics of agricultural crops that show the period of their • Some crops need more water than others. growth, season and average amount of water • The age of the crop is important, because needed, as shown in Tables 5–7 in the Appendix. most crops need less water at the beginning of Before referring to these tables, farmers should their growth than in later stages, so the water consider the following: requirements of the crop have to be met at • The tables show the water requirements each stage. for the agricultural crop and not the irrigation • The higher the salt concentration, the more needs, so farmers must adjust them based on water the crop requires. the efficiency of the irrigation method they are using. • Weather and climate conditions in each region, such as humidity and wind speed, are • Water requirements vary when several crops important. are intercropped with each other, so farmers should seek out an expert’s opinion on • The type and nature of changes in soil affect agricultural crops. crops differently. • The irrigation method used affects the Many other factors affect the water requirements irrigation requirements of the crop. As such, of agricultural crops. In general, however, the it is better to use modern irrigation methods, average amount of water needed to irrigate an as they are more efficient (Figure 2) and help acre of agricultural land is 25–50 m3 per day. conserve and maximize water use. 4 4. Agriculture and aquaculture in arid areas Some might think that farming and aquaculture Of course, this does not mean that farmers should are not possible in arid areas because of a lack of rush to farm in the desert, as there are important water and land that can support such activities. factors to consider: However, some factors can make these activities possible, and even favorable: • Farmers should get a soil and water analysis to determine their suitability for aquaculture • In many areas, there is enough well water or and agriculture. groundwater in the desert to have sufficient reserves to support farming and fish culture, • They must know the changes in climate and related activities. and weather. • Water treatment facilities that make water • It is important for them to determine the best reusable will prolong farming activities. methods to save and conserve water. • Aquaculture is considered a method of Usually, government institutes periodically release land reclamation. documents about weather and climate changes and soil and water properties in different regions. • Water discharged from fish ponds is rich in They even go as far as recommending areas that nutrients that can support the poor soil of are best suited for reclamation and the water the desert. requirements for each crop. Farmers can simply follow these instructions and save themselves the cost of getting an analysis and avoiding the risks that come with experimental farming. 5 5. Irrigation strategies and considerations There are four main methods that farmers For integrated fish farming systems, farmers should can use for irrigating agricultural crops: follow these instructions to avoid problems that surface irrigation (flood irrigation), pressurized can arise when using advanced irrigation methods: irrigation (drip and sprinkler irrigation), subsurface irrigation and localized irrigation. • Use a separate sedimentation tank (Figure 3) to collect water for irrigating crops. The water is The most common of these are flood irrigation drawn from the bottom of the culture tank into and drip and sprinkler irrigation. For integrated the sedimentation tank, where precipitated farming systems, it is best to avoid flood irrigation, waste is located, to avoid harming the fish. as it is the least efficient method (Figure 2). • Place nets over the canal pipes that connect the two tanks. The size of the mesh should Sprinkler irrigation is preferred for field crops such be large enough to allow solid waste to pass as alfalfa, wheat and barley, while localized drip between the two tanks, but small enough that irrigation is best for spaced crops, such as trees, the fish cannot pass through. The water used beetroot, corn and vegetables. These methods for irrigation is drawn from the top layer of the are much more efficient than the others. sedimentation tank to avoid sediment at the bottom that could block the pipes. • Use a mechanical filter to remove residual sediment in the water. 100 90 80 70 60 50 40 30 20 10 0 Surface Surface Sprinkler Sprinkler Drip/trickle (traditional) (advanced) (day) (night/morning) Irrigation methods Figure 2. A comparison of the efficiency of different irrigation methods. 6 Percentage Water exit Sedimentation tank Fish tank Water entrance Figure 3. A fish tank and sedimentation tank, with a mesh net at the entrance of the pipe connecting the two tanks. Farmers can use chemical compounds to dissolve • The water used must be suitable for the type suspended solids and sediment to avoid blocking of crop and fish species cultured. pipes or sprinklers. They can also collect any sediment that has settled at the bottom of the • The effect of enriched water on crops might tank and use it as fertilizer for plants. For example, not have observable results in the first planting phosphoric acid has a dual-purpose. It is used to season, because the elements are stored in clean out irrigation hoses while at the same time the soil over time. The effect of these fertilizers acting as a fertilizer for plants, as it is a good source appears in the following seasons. This is known of phosphorous. as the land storage effect. • Farmers must be flexible when using water. The following are concerns that farmers should For some crops, they should stop irrigating take into account regarding irrigation in integrated their crops in winter and for pre-harvest aquaculture-agriculture systems: fasting. They should also consider draining • Drip and sprinkler methods require highly the water from their fish tanks directly into the efficient filters to maintain the irrigation system. drainage canal. • Sometimes, the drained water from the fish • Farmers can use water that is relatively high tanks is more than what the crops need. in salt (3000–7500 ppm) to cultivate crops that can tolerate salinity, such as olives, • Water drained from the fish tanks contains a pomegranates and palm trees. However, they high percentage of dissolved nitrogen, which must chose a type of farmed fish that can is an essential element for crops at the start tolerate the same salinity. As such, farmers of their growth period. However, agricultural must take into account that continuous crops need other elements for growth in the irrigation could raise the salinity level in the following stages, the most important being soil. To overcome this problem, farmers are calcium, phosphorus and potassium. These advised to consult an irrigation specialist. elements, in their dissolved form, can be added to the irrigation water to compensate for its deficiency. 7 6. Designing a fish culture unit 6.1. Size However, they are less efficient from the perspectives of management, drainage and waste removal. The size of the fish culture unit and the expected Circular or octagonal ponds are considered the best, production capacity must be proportional to the because they are easier to manage and to remove area of agricultural land intended for use and its waste. The advantage of octagonal ponds is that water requirements. The size of the pond should they aerate the water better because they have eight be neither too big that it results in a lower rate of angles and are easier to build than circular ponds. water exchange, nor too small that it affects the volume of water available for the fish. The more With rectangular and square tanks, it is better to farmers can increase the exchange rate, the better irrigate from the top of the tank to stir the water it is for fish growth. better, while drainage should come from the opposite side of the tank to remove solid waste The size of the culture unit affects two important at the bottom. Drainage in circular tanks differs factors: the water exchange rate and the from the traditional method, as these tanks slope sustainable volume of water. toward the center where the drainage hole is. The slope helps stir the water inside the tank so that it The rate of water exchange increases in small units is easier to collect and get rid of waste. compared to large ones. The higher the rate, the better it is for fish growth. The sustainable volume of water is the amount that must be maintained at all times in order to preserve the lives of the fish. The sustainable volume will be as large as the size of the culturing unit, so farmers have to determine the size of the culture unit to maintain the balance between these two factors. For optimal water use efficiency, the volume of the fish culture tank may vary according to an average daily water use for crops of m3/day. For example, for five acres of land, with a daily water use rate per acre of 20 m3/acre for irrigation, a water tank of 100–200 m3 is optimum bearing in mind that the water depth suitable for tilapia culture ranges from 1 to 2 m. Plate 1. Rectangular polyethylene-lined pond. 6.2. Types Fishponds are built for two reasons: for growing fish or as a water reservoir for irrigating crop- cultivated land. There are two main types of ponds: concrete and plastic-lined. 6.2.1. Concrete ponds Concrete ponds are better for sandy soil that cannot retain water for a long time. These ponds can be square, rectangular, circular or another shape. Circular is best. Rectangular or square ponds are best for large areas of land, as they leave more space for fish farming. Plate 2. Circular concrete pond. 8 Photo credit: Ibrahim Elsira/WorldFish Photo credit: Ahmed Nasr-Allah/WorldFish 6.2.2. Plastic-lined ponds For this type of pond, a sheet of polyethylene is used to cover the entire bottom. Like concrete ponds, these ponds are used for sandy soil that cannot retain water. However, plastic-lined ponds are less expensive than concrete ponds. They are also suitable for relatively large areas, and they lower the amount of water that leaks into the soil. A high density, 1000 micron thick polyethylene tarpaulin has a shelf life of 10 years. The soil has to be free of any gravel or sharp edges that could puncture the tarpaulin and lead to water leaks. Never use sharp tools or materials that could puncture the plastic layer. Plate 3. A pond lined with plastic. When building a fishpond, another option is to use bricks topped with a layer of cement Farmers should consider the following when to cover the dikes and the bottom. This designing a fishpond: technique is relatively less expensive than concrete ponds, but farmers should consult • Make the best use of uneven ground surfaces, a specialist before starting construction. as the level of the ground will affect both irrigation and drainage (Figure 4). Irrigation pipe Irrigation canal Net over the irrigation outlet Stopcock Pond water level Pond bottom Figure 4. Recommended design for pond irrigation. 9 Photo credit: Ahmed Elewa/WorldFish • When designing a fishpond, direct the drainage • Make sure the bottom slopes toward the water straight into the drainage canal so that drainage canal to make it easier to drain the the water can be changed regularly, regardless water and collect waste. Ensure the irrigation of whether it is needed for irrigation. When inlet is opposite the drainage outlet. irrigation water is needed, use the drainage water. When irrigation water is not needed, • Build a canal around the pond and connect drain the water directly into the drainage canal. it to the pond to circulate the water. The movement of the water in the canal will cause • When building irrigation and drainage canals, waste to precipitate and increase the water use water from the top for irrigation (Figure quality so that it can be reused. Clear the canal 4) to stir the water more and to increase the of sediment regularly. level of dissolved oxygen (DO). For drainage, use water from the bottom, where waste accumulates. Plate 4. Using irrigation water from the top of a pond. 10 Photo credit: Ibrahim Elsira/WorldFish 7. Fish culture 7.1. Cultured fish species First, calculate the biomass of the harvested fish at the end of the season: Many fish species are suitable for farming. In Egypt, Nile tilapia and African catfish are among • The number of fish per kilogram multiplied the most common and widespread species. They by the number of kilograms expected to be are suitable for integrated aquaculture-agriculture harvested per cubic meter. For example, if systems for the following reasons: there are 2 fish/kg and 10 kg of fish/m3 are expected, then the number of harvested fish • They can tolerate low levels of DO in water would be 20/m3 (2 X 10 = 20 fish/m3). longer than other species. They also can tolerate high rates of intensification. Second, calculate the survival rate during the • They are in demand at the markets year-round. season: • Seed is available for almost the whole year. • The survival rate is based on several factors, the most important of which is fish size. The • They grow fast and can tolerate changes in larger the fish, the lower the mortality rate. environmental conditions better than other For example, if the weight of the fish when species. cultured is more than 20 g (fingerlings), the mortality rate would be 10%, increasing 7.2. Culture season gradually until it reaches 30% for lower weights (e.g. less than 1 g). The culture season for both tilapia and catfish starts when the temperature rises, from March • Assuming that the mortality rate is 10%, the until November. The length of the culture season number of fingerlings to be cultured would increases or decreases according to the location, be as follows: Number of harvested fish + climate and weather. number of expected loss (number of harvested fish x loss percentage). For example, if 20 fish 7.3. Fish size are harvested, the farmer must culture 22 It is better to culture large fingerlings to avoid fingerlings per cubic meter: 20 + (20 x 0.1) = 22 high losses that occur with seed. Fingerlings also fingerlings/m3). produce a higher percentage of ammonia than seeds. Ammonia is an important factor for crops, It is worth mentioning here that a fish tank has a especially at the beginning of the planting season, maximum carrying capacity for production. This which requires high amounts of nitrogen. depends on several factors, such as water quality, feeding rate, availability of aeration devices, 7.4. Fish source duration of its operating hours and management. For example, if customers prefer small fish, farmers The fish source must be reliable and trustworthy. who want to produce 250 g fish will have to double For Nile tilapia, all male fingerlings are better, the number of fingerlings (22 fingerlings/m3 → 44 because they grow faster and do not reproduce in fingerlings/m3). Production will remain at 10 kg/m3, the pond. but the size of the fish produced in the same period might have to be halved (500 g/fish → 250 g/fish). 7.5. Stocking rate or carrying capacity Farmers must also take into account the Farms can start a culture cycle based on the average relationship between field irrigation requirements productivity in farms where the water and weather and the intensity of fish farming. The higher the conditions are similar. For example, if the average rate of water changes in the pond, the greater the production in a neighboring farm is 10 kg/m3, and the chances of intensifying the production (an expert average size of the resulting fish is 500 g per fish, then in fish farming ought to be consulted). it is possible to calculate the stocking rate as follows: 11 8. Fish nutrition 8.1. General criteria • Floating feed is recommended because it minimizes feed loss and is simple to determine • Feed is important for fish growth, especially when to stop feeding, as it is easy to see when in intensive fish farming, as it is the main the fish stop eating. source of nutrition. It is a source of ammonia, either directly, through the decomposition • For small fish, feed them 1–2 mm pellets that of feed in water, or indirectly, through waste are 30%–35% protein, and give it to them three from fish feeding and organic matter. In to four times daily at a rate of 5%–10% of their both cases, ammonia enriches the water weight. For large fish, they require 3 mm pellets and supplies it with important elements, that are 25%–30% protein, given one or two especially nitrogen, that are needed for plants times daily at a rate of 2%–5% of their weight. to grow. However, farmers must make sure not to use too much feed so that the level • When throwing floating feed to fish, use a of ammonia does not get too high and that “floating” ring made of hoses or pipes to trap feed is not wasted. To dispose of this excess the feed inside it to stop the feed from drifting ammonia, farmers either have to replace to the sides of the pond. This will make it easy some of the water to prevent a decline in for fish to reach the food and avoid being water quality or use it for agricultural crops, preyed upon by birds, as they won’t have to which can benefit from this excess nitrogen. approach shallow areas near the pond's sides. • Feed is the largest part of production costs, so • Follow the proper feeding method for the type farmers should buy good quality feed produced and size of fish cultured. Artificial fish feed is specifically for the fish they are culturing. available in different granule forms and pellet diameters (Table 3). The size of the pellets • Deal directly with the factory, not a mediator, depends on the size of the mouths of the fish. to avoid fraud or bad storage. Otherwise, only deal with a trusted mediator. • Chose the proper granule size. As the sizes of fish often vary in a single pond, it is necessary • When purchasing feed, makes sure the to mix two or more pellet sizes to cover the ingredients and production date are shown nutritional needs of every size. To avoid large on the data card and list the levels of protein, fish from eating the feed for smaller fish, place energy, calcium, phosphorous and vitamins. the small granules in a special feeder that only small fish can access. • Analyze a sample of the feed, if possible, to ensure its quality, and contact the factory if necessary. How the sample is taken is an Age/fish weight Pellet diameter (mm) important to determine the feed quality. As such, several conditions must be observed Larvae to 10 days old >0.5 when taking a sample: (i) the sample should 10–30 days 0.5–1 represent the entire feed stock, (ii) prepare the sample according to the analyses needed and 1–30 g 1 (iii) preserve the sample to last long enough to 20–120 g 2 complete all required analyses. 100–250 g 3 • Store various feeds separately in a suitable, well-ventilated warehouse that keeps out pests 250 g 4 and rodents. Table 3. The relationship between the weight/age • Keep records of feed purchases, including the of tilapia and the diameter of feed pellets type, source, price and quantity. used for feeding. 12 • To minimize feed waste, use a demand feeder • plan the harvest date according to the sample (Plate 5), which releases feed only when the fish size and growth rate; are under it looking for food. Fiberglass feeders are best because they last longer than those • taste the fish before the harvest to judge the made of sheet steel, which rusts quickly because quality before selling them; of the humidity associated with fishponds. • determine the health of the fish according to the relationship between their weight and length. 8.2. Feeding program Follow these steps to obtain a fish sample from a Feed fish until they appear satiated. The best way specific pond: to determine this is to use floating feeds, as the farmer can see how the fish are feeding. If the • When taking the sample, avoid times of high fish eat all of the feed within 20–30 minutes, they temperatures and extreme cold, as well as fog do not need any more food. However, if there and strong winds. is still feed left over after 30 minutes, reduce the equivalent amount of feed that remains uneaten. If • Take the sample while feeding the fish, as this the fish eat all of the feed in less than 10 minutes, is the best time to collect the fish. increase the amount of feed 10% per day until • Make sure the number of fish in the sample the fish appear satiated after 20–30 minutes. is sufficient and comes from different areas of the tank. 8.3. Monitoring fish growth • Place the fish gently into small containers, such Taking fish samples regularly is necessary to as buckets. know how the fish are doing, their growth rate and the quality of the feed used and to • Weigh the fish in small quantities to avoid determine how much feed is needed per day. crowding and fatigue. Taking samples regularly is important to • Record the data from the samples and feed • monitor the growth of fish in each tank; quantities used for each tank. • calculate the amount of feed needed • When taking samples to screen for diseases, do according to weight gain; not return the fish to the pond. • evaluate the quality of the feed by Be sure not to stress the fish in order to maintain their calculating the increased weight of the liveliness and to avoid infections. Avoid sampling fish fish as a result of using a certain amount (i) when there are problems with the water quality of feed (feed conversion ratio); in the pond, (ii) if the fish are diseased, (iii) when the pond water is too turbid, and (iv) when it is raining. • estimate the expected amount of fish production; Plate 5. Feeding fish manually. 13 Photo credit: WorldFish 9. Water management in fishponds 9.1. General criteria 9.1.1. Water requirements • Identify the specifications of the water There are two types of water sources: groundwater used in the farm, its quantities and suitability and surface water. for fish culture and production and crop irrigation practices. Surface water, such as rivers, lakes and streams, is affected by temperatures changes, depending on • Fish do not consume the water but only the weather conditions. When temperatures drop maximize its use. in winter, farmers have to stop feeding their fish. • Analyze the source of the farm water, They also need to replace the water frequently in including salinity, DO, pH, ammonia, nitrite, order to keep the temperature of the pond from nitrate, phosphorous, iron, potassium and, dropping too low. most importantly, pollutants. Examples of groundwater include well and • Monitor the pond’s water quality parameters spring water. Unlike surface water, groundwater to determine the appropriate management maintains a constant temperature throughout the method and whether to replace or aerate the year, so farmers do not need to stop feeding their water. This is also essential to determine the fish during the winter. Groundwater also reduces impact on crops. the fatigue of fish caused by temperature changes. • Make sure the water depth is optimal If using spring water, however, farmers must make for fish growth. sure to measure levels of DO, salinity and iron. • Use groundwater to keep the temperature As shown in Table 4, groundwater is one of the stable and lengthen the growth period best types of water for fish farming. It contains low of the fish. levels of pathogens and pollutants, so its microbial content is low. However, groundwater lacks DO, • As much as possible, reuse the water after so farmers will need to use devices to increase its it is filtered to conserve resources. This requires oxygen content. using mechanical and biological filters as well as aeration devices, depending on The size of the water tank must be twice the intensity levels. amount of water needed for the fish. This is to maintain a sustainable volume of water for the fish. Comparison Groundwater Surface water Temperature The temperature remains steady throughout the year. The temperature varies according to weather conditions. Dissolved oxygen DO is low, so ventilation is required. DO levels are sufficient. Undesirable fish It is free of unwanted fish or any other organisms. A mesh net should be placed over the irrigation source to stop unwanted fish from entering. Wintering The temperature does not change, so greenhouses The temperature needs to change, if can be used to maintain the temperature. shelter or heating is not available. Toxic elements Water analysis is necessary to ensure the water is Water analysis is preferred, but the risk of suitable and free from toxic elements or metals. toxic elements or metals is low. Table 4. Comparison between groundwater and surface water. 14 9.1.2. Water exchange rate • Using aeration equipment (Plate 6) in ponds helps direct waste to the drain. If the devices The following factors determine the rates for are placed properly, they can help discharge replacing water in a fish production unit: the waste out of the pond. • fish density (biomass) • Consult a specialist to determine whether the • water requirements for crops during pond needs aerators or paddlewheels to meet irrigation periods its oxygen requirements and to know when and how long to use them. • amount of feed added to the tank • The higher the density of fish and biomass • DO levels in the water in the pond, the more aeration is needed. • availability or absence of aeration devices Intensive culture ponds require permanent aeration. • amount of organic waste and solid sediment in the tank • In high-density culture units, measure the ratio of DO daily and use the aeration system • water temperature regularly whenever the ratio falls below its optimal rate. This will keep the fish from • vitality of fish and fish diseases suffocating and maintain their growth rate. • algal bloom. • For tilapia, the percentage of DO in the water should be no less than 5 mg/L. Since the ratio 9.1.3. Aeration of DO in the water decreases sharply during the • Aeration increases the percentage of DO night and reaches its lowest level before sunrise, in the water. It is the most important factor farmers must aerate their ponds overnight. for maintaining the vitality of the fish and improving their appetite. Plate 6. Paddle wheel aerator. 15 Photo credit: WorldFish 10. Fish health Preventive measures include several stages. 10.3. Fish growth stage • Place screens over the water inlet and 10.1. Pond preparation drainage pipes to keep undesirable • Get rid of floating plants and fish waste, such fish out of the pond. This will also help as dead fish. control birds, which can carry diseases. • In case of previous diseases, disinfect the fish • Pay attention to water quality parameters. For using quicklime, formalin or chlorine. example, monitor the DO and temperature daily. Other parameters, such as ammonia 10.2. Incubating fry and nitrite, can be monitored weekly. • Be sure to purchase fry from a reputable • Give the fish high quality feed that source. Make sure the fry are of high vitality, meets their nutritional requirements. uniform in size and free from apparent • Store feed properly. Avoid storing it pathological symptoms. for a long time to prevent damage • Use feed that is suitable for the age of the fry. and avoid the growth of fungus. Powdered is best. • Do periodic sampling to keep tabs • Follow proper preventive measures when on the health of the fish. receiving the fry, especially if they are brought • Follow proper hygiene measures when from different regions. As an example, getting rid of dead fish in the farm. Use an place the fry in a small separate pond isolated area to dispose of dead fish safely, and leave them for several days without whether by burning or burial. If burying feeding. If they show any pathological fish, do so at an appropriate depth and symptoms, they are infected. If not, spray with quicklime afterward (Figure 5). transfer them to the grow-out ponds. Generally, it is highly recommended to observe the behavior of the fish in the pond at all stages and consult with a fish disease specialist as soon as there is a change in behavior or appearance of mortality. • Isolated area Soil 0.6 m • At least 30 m from any other surface water Quicklime • Pit bottom is 1.2 m above the high water table Dead fish • Cover with quicklime • Covering carcasses with about 0.6 m of soil 1.2 m above water table Source: Nasr-Allah et al. 2021. Figure 5. How to dispose of dead fish hygienically. 16 11. Fish harvesting and post-harvest procedures For integrated aquaculture-agricultural systems, • During sorting, grade the fish in accordance partial harvesting is best because this keeps the with marketing sizes. water in the pond in order to irrigate the crops. As such, it is important to use nets when doing After grading, place the fish in the appropriate a partial harvest so as not to drain the water marketing packages according to consumer completely. If a full harvest has to be done, make preferences. Use packages of good quality and sure that the canal or irrigation system can absorb healthy specifications. the amount of water to be drained. In addition, before every harvest, farmers must be aware of the When packaging fish for sale, follow these measures: current market trends and expected selling prices to determine how many fish to harvest. • Lay the fish lengthwise, and stack them without bending the body. Follow these procedures when harvesting fish: • Do not put too many fish into the box. Boxes • Stop feeding the fish at least 1 day before should be no more than 30 cm high. the harvest so that they can empty their • Make sure the fish do not touch the sides of digestive tract. the box. Instead, place ice on the sides. • Before draining the pond, close the irrigation • Stack the fish in layers alternately with layers of inlet and install nets over the drainage pipe. crushed ice to avoid damage. • Eliminate aquatic plants and solid plankton growing on the bottom of the pond, as this If selling live fish, weigh them and then place can hinder the movement of the nets. them in clean oxygenated water tanks fitted with an oxygen cylinder or air pump. If the fish are to • Taste test the fish before the harvest to make be sold at an open market, use crushed ice to sure that the fish taste good and do not have maintain the firmness and freshness of the fish. unwanted odors. Have sufficient quantities of crushed ice on hand to compensate for ambient temperatures and the • Train workers on how to catch, sort and handle distance of transportation. fish properly. • Drain the pond quickly, and pump the water into Cover the fish boxes with clean linoleum the drain age canal, not at the source of irrigation. during transportation to avoid exposure to direct sunlight and to keep the ice from • When harvesting, avoid exposing the fish to melting quickly. Transport the fish during the high heat or extreme cold in the pond. night or in the early morning, and do so in a • In the summer, harvest the fish before sunrise refrigerated vehicle. It is always best to transport or at sunset to avoid high temperatures when the fish as soon as possible to the market. handling and transporting the fish. If using ice to transport the fish and maintain • Transport the fish to the washing and sorting freshness, keep in mind that the amount of ice station as quickly as possible. used must be proportional to the amount of fish being transported, as well as the ambient • Clean all tools and containers used to handle temperature. This should be done immediately and sort the fish. after harvest. The faster the fish are cooled, the • Wash the fish thoroughly with clean water to longer they stay fresh. maintain quality. • Use crushed ice to keep the fish cool while washing them. 17 An alternative way to treat fish after harvest Farmers who use this method can transport the is to submerge them in cold water (0°C–4°C) fish to the market in a refrigerated vehicle without immediately after harvesting. This will induce heat having to add ice. shock and keep the fish fresh before they are sold. Plate 7. Partial harvest activities in integrated tanks. 18 Photo credit: Ahmed Nasr-Allah/WorldFish 12. Marketing • Be aware of the different markets, price • Take into account pre- and post-harvest changes and seasonality. procedures, and follow proper methods to ensure the fish stay firm and fresh until they • Time harvests to take advantage of increased reach the markets. market demand in some seasons to achieve the highest return. • Communicate with marketing associations and other producers to save time and energy and • For partial harvests, determine the quantity potentially reduce costs. to harvest according to the needs of local markets. Focus on selling live fish to maximize • Maintain good relations with producer returns and reduce costs. associations, various fish market administrative groups and fish marketing groups. Fish • Harvest fish that are the size that target producer associations are particularly helpful markets prefer. because they study the needs of the market • To maintain quality, keep fish as fresh as and can help market products in different possible, bearing in mind that consumers have places inside and outside the country. different taste preferences. Plate 8. Stacking fish carefully without bending the body to avoid damage. 19 Photo credit: Ahmed Nasr-Allah/WorldFish 13. Social responsibility Farmers should follow these recommendations to • Share media promotions for fish farms that support permanent laborers on the farm and for explain their safety and security to consumers the community around it: and the safety of the procedures used in their production. • Give fish to people far away from traditional fish production areas at affordable prices and • Cooperate with neighboring farms to keep in good condition. facilities, water canals and drainages intact and in good condition and help maintain them. • Allocate part of the farm’s production for sale to the residents of the surrounding area at a • Provide adequate facilities for the subsistence wholesale price. of farm workers. • Show the benefits of integration between the • Ensure that workers are provided with the fish and crops to the local community. necessary supplies, such as protective gear and clothing. • Encourage the employment of youths and women. • Train workers on how to use chemicals and medicines safely. • Do not employ children. • Organize fairs and events to showcase • For irrigation, use water that contains high day-to-day fish culture and crop culture levels of fertilizer elements. This will reduce system work activities, where participants the need for agriculture fertilizer for crops and could have access to the farm's records to reduce the impact on the environment. get a sense of the day-to-day management. • Contribute to the social and health care of the This could include information on daily farm workers and their families. water quality parameters, fish behavior, amount of water used for irrigation, incident • Donate to charities and community reports, waste management, etc. development projects in the areas around the farm. • Train the workers responsible for feeding fish to identify water quality warning signals and • When promoting products, be sure to mention take appropriate measures. that there are employment opportunities available on the farm. • Train workers on biosecurity measures. • Employ residents from some of the areas around the farm. • Encourage consumers to eat locally produced fish to help reduce the consumption of imported fish of unknown origin. In addition, explain the differences between fresh and frozen fish. 20 Notes 1 For more details and information about fish farming, please refer to the 2016 issue of the Fish Farmers Guide about the best management practices for fishponds in Egypt, prepared by WorldFish. References Ashraf A, Habeb O, Nasr-Allah A and Charo-Karisa H. 2019. Best practice of integrated of aquaculture and agriculture. Cairo, Egypt: WorldFish. Guideline 1. https://hdl.handle.net/20.500.12348/3935 Bakeer MN. 2009. Integration of aquaculture and agriculture. Cairo, Egypt: GAFRD. Hasan H. 2016. Manual for culturing fish in the desert. Cairo, Egypt: Eid Ala Eid Institute. Nasr-Allah A, Dickson M, Al-Kenawy DA, Ibrahim N, Ali SE and Charo-Karisa H. 2021. Better management practices for tilapia culture in Egypt. Penang, Malaysia: CGIAR Research Program on Fish Agri-Food Systems. Manual: FISH-2021-03. https://hdl.handle.net/20.500.12348/4698 Nasr-Allah A, Kenawy D, El-Naggar G, Beveridge M and Heijden PGM van der. 2012. Evaluation of the use of fresh water by four Egyptian farms applying integrated aquaculture – agriculture. Wageningen, The Netherlands: Wageningen University and Research Centre. https://hdl.handle.net/10568/32730 Pillay TVR and Kutty MN. 2005. Aquaculture Principles and Practices. (2nd ed.). Oxford: Blackwell Publishing. Sadek S. 2011. An overview on desert aquaculture in Egypt, 2010. Hermosillo, Mexico: FAO. WorldFish and Central Laboratory for Aquaculture Research. 2018. Workshop on integrated aquaculture and agriculture. Cairo, Egypt, June 20–21, 2018. 21 Appendix 1. Water requirements for crops in Egypt Crop Area January February March April May June July August September October November December Total Mangoes Delta 120 170 255 277 319 383 364 329 312 276 172 130 3107 Middle Egypt 150 212 319 347 399 479 455 412 390 345 215 163 3884 Upper Egypt 185 263 395 430 495 594 564 511 484 427 266 202 4816 Olives Delta 74 103 133 162 206 251 280 265 221 192 147 118 2152 Middle Egypt 92 129 166 203 258 313 350 332 276 240 184 147 2690 Upper Egypt 114 160 206 251 320 388 434 411 343 297 228 183 3335 Bananas Delta 240 360 456 504 600 648 600 528 456 408 336 240 5376 Middle Egypt 300 450 570 630 750 810 750 660 570 510 420 300 6720 Upper Egypt 372 558 707 781 930 1004 930 818 707 632 521 372 8333 Palm trees Delta 80 110 140 168 224 244 223 198 179 127 115 114 1923 Middle Egypt 100 138 175 210 280 305 279 247 224 158 144 143 2404 Upper Egypt 124 171 217 260 348 379 346 307 278 196 179 177 2981 Citrus fruit Delta 108 153 232 272 345 402 368 359 303 272 166 120 3100 Middle Egypt 134 191 290 340 431 503 460 449 379 339 208 150 3875 Upper Egypt 167 237 360 422 535 624 570 556 470 421 258 185 4805 Deciduous Delta 0 0 170 255 361 428 383 468 406 276 160 0 2906 fruit Middle Egypt 0 0 212 319 451 535 479 585 507 345 199 0 3633 Upper Egypt 0 0 263 395 559 664 594 726 629 427 247 0 4505 Source: Egypt’s agricultural weather stations (Kafr Elsheikh-Suds-Shandweel). Table 5. Estimated water requirements for some fruits (m3/feddan/month). 22 Crop Area January February March April May June July August September October November December Total Wheat Delta 229 326 434 490 123 0 0 0 0 0 62 179 1844 Middle Egypt - - - - - - - - - -- - - 2517 Upper Egypt 570 665 715 239 0 0 0 0 0 0 372 505 3066 Sugar beet Delta 361 441 526 0 0 0 0 0 0 362 320 344 2353 Middle Egypt - - - - - - - - - - - - 3291 Upper Egypt - - - - - - - - - - -- - 4452 Alfalfa/ Delta 297 365 483 612 302 0 0 0 0 0 249 300 2609 clover Middle Egypt - - - - - - - - - - - - 3762 Upper Egypt 588 622 769 507 0 0 0 0 388 679 701 655 4909 Maize Delta 0 0 0 0 132 510 821 757 238 0 0 0 2459 Middle Egypt - - - - - - - - - - - - 3515 Upper Egypt 0 0 0 0 344 285 1160 1139 786 0 0 0 3714 Fava Delta 269 381 495 273 0 0 0 0 0 0 61 179 1658 beans - - - - - - - - - - - - - 1729 Upper Egypt 284 0 0 0 0 0 0 0 508 679 680 609 2151 String Delta 91.2 261.6 566.4 480 235.2 0 0 0 0 0 0 0 1634 beans Middle Egypt - - - - - - - - - - - - - Upper Egypt 218 516 769 567 0 0 0 0 0 0 0 0 2070 Source: Egypt’s agricultural weather stations (Kafr Elsheikh-Suds-Shandweel). Table 6. Estimated water requirements for some field crops (m3/feddan/month). 23 Crop Area January February March April May June July August September October November December Total Tomatoes Delta 91.2 228 494.4 609.6 628.8 566.4 0 0 0 0 0 0 2618 Middle Egypt 114 285 618 762 786 708 0 0 0 0 0 0 3273 Upper Egypt 142.5 356.25 772.5 952.5 982.5 885 0 0 0 0 0 0 4091 Potatoes Delta 115.2 261.6 566.4 609.6 590.4 0 0 0 0 0 0 0 2143 Middle Egypt 144 327 708 762 738 0 0 0 0 0 0 0 2679 Upper Egypt 180 408.75 885 952.5 922.5 0 0 0 0 0 0 0 3349 Cucumbers Delta 136.8 261.6 472.8 576 0 0 0 0 0 0 0 0 1447 Middle Egypt 171 327 591 720 0 0 0 0 0 0 0 0 1809 Upper Egypt 213.75 408.75 738.75 900 0 0 0 0 0 0 0 0 2261 Eggplants Delta - - - - - - - - - - - - 3353 Middle Egypt - - - - - - - - - - - - 4191 Upper Egypt 288 0 0 0 0 0 0 495 721 719 594 536 3353 Peppers Delta 91.2 352.8 705.6 710.4 787.2 739.2 705.6 0 0 0 0 0 4092 Middle Egypt 114 441 882 888 984 924 882 0 0 0 0 0 5115 Upper Egypt 142.5 551.25 1102.5 1110 1230 1155 1102.5 0 0 0 0 0 6394 Source: Egypt’s agricultural weather stations (Kafr Elsheikh-Suds-Shandweel). Table 7. Estimated water requirements for some vegetable crops (m3/feddan/month). 24 About WorldFish WorldFish is an international, not-for-profit research organization that works to reduce hunger and poverty by improving aquatic food systems, including fisheries and aquaculture. It collaborates with numerous international, regional and national partners to deliver transformational impacts to millions of people who depend on fish for food, nutrition and income in the developing world. The WorldFish headquarters is in Penang, Malaysia, with regional offices across Africa, Asia and the Pacific. The organization is a member of CGIAR, the world’s largest research partnership for a food secure future dedicated to reducing poverty, enhancing food and nutrition security and improving natural resources. For more information, please visit www.worldfishcenter.org 25