Supplemental C Addressed the pH Conundrum in Sustainable Marine Aquaponic Food Production Systems

Abstract

pH is the major issue that concerns all producers in aquaponics, as the main three organisms (aquatic animal, plant, and microbes) have different preferences. Additional C is a potential approach to amend the growing environment and improve shrimp and plant growth, and microbe establishment. Aquaponics under saline conditions has, however, not been studied in detail in regard to the effect of pH and additional C. In this study, we evaluate the impact of pH and additional C on the growth of Pacific whiteleg shrimp and five edible plants (three halophytes and two glycophytes) in marine aquaponic systems using nutrient film technique (NFT). The results indicated that plants grow better in both pH 6.5 treatments; however, additional C improved the growth in pH 7.5 + C treatment and had similar yield to lower pH treatments. The results indicated both pH and additional C had little impact on shrimp growth. In conclusion, adding C can be a practical solution to the pH conundrum for marine aquaponics. Appling additional C was suggested for the operation of marine aquaponic food production system when the pH is high.

pH Dynamics in Aquaponic Systems: Implications for Plant and Fish Crop Productivity and Yield

“…Aquaponic nutrient solutions are not as easy to maintain as hydroponic solutions. The aquaponic solution is affected by many factors, such as fish feeding rate, hydraulic loading rate, and pH [10,11]. Yang and Kim [2] analyzed three different feeding rates and found that a uniform feeding rate can enhance crop yield and/or quality in aquaponics by increasing initial nutrient availability and overall nitrogen-use efficiency of the system [2].…”

Marine Aquaponics: An Ocean Full of Potential for Sustainable Food Production

“…Optimal pH for ammonia and nitrite oxidizing bacteria is 7.3-8.0. We described this challenge as the "pH conundrum" [4]. Aquatic animals tend to be tolerant of pH ranges outside optimal, but suboptimal pH for plants can reduce nutrient uptake from the environment.…”

“…Aquatic animals tend to be tolerant of pH ranges outside optimal, but suboptimal pH for plants can reduce nutrient uptake from the environment. Using a flocponic system (biofloc is a term describing the purposeful addition and maintenance of a complex bacterial community and use of biofloc approaches in aquaponics has been termed flocponics) with Pacific white shrimp and red orache, minutina, Swiss chard, okahijiki, and kale, we identified that some plants overcame decreased growth at pH 7.5 when additional carbon was added to the system [4]. Further research is needed in the area of optimal water quality that optimizes healthy populations of all three taxa.…”

Assessment of the development of Lactuca sativa Batavia Aficion in hydroponic and aquaponic systems

“…The prospects of using both technologies in Ukraine and the positive environmental and economic conditions were discussed by Y.-T. Chu et al (2023). They noted that there are various methods of hydroponics, such as drip irrigation techniques, film systems and root immersion systems, which help to precisely control the nutrition of plants and create optimal conditions for their growth.…”