Water quality significantly influences the growth, survival, and biomass of aquatic organisms, with specific indicators tailored to the needs of fish (El-Kady et al., 2022). Nitrites, nitrogen, pH, and nitrates are vital water characteristics impacting fish growth (Ciji & Akhtar 2020). Managing these parameters is essential for aquaculture production growth, promoting optimal fish growth and reducing stress (Fleckenstein et al., 2020). Water filtration choices have lasting effects on reusability and properties (Fleckenstein et al., 2020). Utilizing different plants for filtration, such as strawberries, peppermint, cucumber, and okra, enhances water quality, as shown by reduced levels of aluminum, chlorine, and nitrogen dioxide compared to control groups (Miguel et al., 2021; Munubi et al., 2022). Moreover, pH stabilization through plant involvement aligns with studies emphasizing plant roles in nutrient uptake and water purification (Guo et al., 2022). Peppermint treatment outperforms strawberry and okra treatments in dissolved oxygen content, underscoring varied plant effects on oxygen exchange (Rahman & Wahab, 2020). Surprisingly, higher total dissolved solids and salinity in peppermint treatment suggest intriguing plant-water interactions warranting further exploration (Martins et al., 2010). Temperature and ammonia-N levels did not significantly differ among treatment groups but remain vital factors affecting aquaponics system dynamics (Mungkung & Saputra, 2022). This study highlights dynamic interactions between vegetables and water quality, supporting plant influence on purification, pH, and oxygen content. The unexpected salinity elevation with peppermint prompts deeper investigation into specific plant-water mechanisms within the broader context of aquaponics literature. The significantly lower survival rate in the control group compared to treatment groups underscores the potential benefits of incorporating filtration plants in aquaponics systems (Miguel et al., 2021). This result aligns with studies emphasizing the role of plant-based filtration in improving overall system health and fish survival (Xiao et al., 2018). The highest survival rate observed in the treatment groups further emphasizes the positive impact of plant integration. This suggests that the utilization of different vegetables as filtration plants can contribute to a higher survival rate of Common carp (Fischer et. al., 2021).
The current study indicates that Common carp exposed to filtration treatments involving strawberry, peppermint, cucumber, and okra exhibited significantly higher weight gain compared to the control group. This is in agreement with the concept that the presence of these vegetables in the system can positively impact fish growth through nutrient assimilation and improved water quality (Robles-Porchas et al., 2020; Rahman & Wahab, 2020). Additionally, Within the treatment groups, okra and cucumber exhibited better body weight gain and specific growth rate compared to strawberry and peppermint (Khanjani et al., 2020). Which suggests specific interactions between these vegetables and fish metabolism (Roques et al., 2020). The best lowest feed conversion ratio was observed in the fish fed with okra and cucumber, although it was not significantly different from strawberry and peppermint treatments, suggests that these treatments were efficient in converting feed into fish biomass ( Sulaiman et al., 2020). This efficiency is crucial for sustainable aquaculture practices. The results are consistent with the idea that certain plants can contribute to enhanced nutrient utilization and reduced wastage (Yang and Kim, 2020). Protein efficiency ratio: The protein efficiency ratio of strawberry was significantly different from peppermint, cucumber, okra, and the control group (Maiti & Singh 2021). This suggests variations in protein utilization among the different treatments. This finding highlights the importance of understanding the nutritional interactions between fish and different plant species in aquaponics systems (Mungkung & Saputra, 2022).The lack of significant effects on hepatosomatic index, viscerasomatic index, and spleen across the different filtration treatments and the control this indicates that the utilization of different vegetables as filtration plants did not have a significant effect on these indices (Krastanova et al., 2022).
Blood plasma indicators like total protein and creatinine were significantly affected by water conditions, reflecting physiological stress in fishes (Shahjahan et al, 2022). Limited direct comparisons exist for plasma biochemistry in Common carp exposed to different aquaponic vegetables, although studies mainly discuss aquaponic systems, water chemistry, and plasma technologies (John et al., 2022). Elevated creatinine levels in peppermint-exposed fish suggest renal and metabolic variations, influenced by factors beyond vegetables. Strawberry and cucumber groups exhibited elevated total protein, albumin, and AST, potentially impacting liver function and protein metabolism, consistent with plant-fish hepatic interaction studies (Verma et al., 2023). Strawberry-fish physiology interactions were implied by notably higher albumin and AST levels. Though not statistically significant, peppermint group's higher ALT levels hint at hepatocellular damage (Fazio et al., 2021). Further investigation in comparison with plant-fish liver studies could elucidate peppermint's effects (Yu et al., 2019). Variable plasma biochemistry among vegetable treatments suggests diverse effects on fish metabolic pathways and organ functions, reinforcing plant-fish health dynamics. Deeper understanding could stem from exploring mechanisms driving observed biochemical variations.
Normal liver histology characterized by intact cellular structure and staining in treatment groups (strawberry, peppermint, cucumber, okra) indicates these vegetables contribute to liver health and integrity, supporting aquaponic plant benefits for water quality, nutrient cycling, and fish well-being (Sulaiman et al., 2022). Control group displayed pyknosis (P) and fibrosis (F) cells, highlighting importance of plant-based filtration and consequences of inadequate nutrient removal. Strawberry and peppermint treatments showed increased hepatocytes (HP), Kupffer cells (KC), division stage cells (DC), suggesting specific vegetable-fish liver interactions, potentially linked to bioactive compounds fostering liver health. Cucumber and okra treatments exhibited normal liver tissues, aligning with growth and plasma findings. Protective effects of certain vegetables on fish liver warrant further investigation.