6.7 CHAPTER SUMMARY

The major advantages of aquaponics over soil agriculture are: (i) no wasted fertilizer; (ii) lower water use; (iii) higher productivity/quality; (iv) ability to utilize non-arable land; and (v) offset of tillage, weeding and other traditional agricultural tasks.

• Plants require sunlight, air, water and nutrients to grow. Essential macronutrients include: nitrogen, phosphorus, potassium, calcium, magnesium and sulphur, Micronutrients include iron, zinc, boron, copper, manganese and molybdenum. Deficiencies need to be addressed by supplying the limiting nutrients with supplemental fertilizer or increasing mineralization.
The most important water quality parameter for plants is pH because it affects the availability of essential nutrients.
The suitable temperature range for most vegetables is 18-26 °C, although many vegetables are seasonal. Winter vegetables require temperatures of 8-20 °C, and summer vegetables require temperatures of 17-30 °C.

Leafy green herbs and vegetables do extremely well in aquaponics. Large fruiting vegetables are also applicable, including tomatoes, peppers, eggplant, and cucumbers, peas and beans. Root crops and tubers are less commonly grown and require special attention.
• Integrated production and pest/disease management uses physical, mechanical and cultural practices to minimize pests/pathogens, and then uses fish-safe chemical and biological treatment in targeted applications, when necessary.
Intelligent planting design can maximize space, encourage beneficial insects and improve production.
Staggered planting provides continual harvest as well as a constant nutrient uptake and more consistent water quality.