Status of Water Quality in Fishponds Surrounding Manila Bay

Abstract

Fishponds around Manila Bay contributed an average of 41.19% of the total aquaculture production in the country. However, massive productions entail the intensification of ponds, which resulted in water quality deterioration. In 2016, Opinion et al. reported water quality in the aquaculture farms around the bay but does not include the other significant parameters required to be monitored, as stated in the DENR AO (2016). Thus, this study investigated the status of water quality in different pond systems surrounding Manila Bay. Extensive, semi-intensive, and intensive fishponds from adjoining provinces of Cavite, Pampanga, Bataan, and Bulacan were monitored throughout the rearing period. Results showed that levels of NH3-N (0.90 mg/L – 2.35 mg/L) and PO4-3 (1.02 mg/L – 2.42 mg/L) were not suitable for the culture of fish. Nevertheless, NO3-N, NO2-N BOD, TSS, DO, pH, and temperature were within the safe levels. Furthermore, results suggested that there should be a regular monitoring of water quality to regulate and manage fishponds surrounding the bay. Finally, strict compliance of the Code of Good Aquaculture Practices (GAqP) must be imposed to achieve water quality standards.

An Overview of Fisheries and Aquaculture in the Philippines

“…Furthermore, the current status of Manila Bay revealed that the levels of PO4 -3 (1.02 mg/L -2.42 mg/L) and NH3-N (0.90 mg/L -2.35 mg/L) were unsuitable for fish culture, although other important parameters like temperature, dissolved oxygen, pH, etc. were within the safe levels (Baldoza et al, 2020). Moreover, high water temperature (>32 °C) was the major challenge that has a significant impact on tilapia aquaculture, particularly in Luzon and Mindanao (Guerrero, 2019).…”

“…To monitor and maintain water quality, there should be a regular assessment or future researches of water quality, especially in aquaculture sites nationwide. In order to attain water quality standards, strict compliance with the Code of Good Aquaculture Practices must be imposed (Baldoza et al, 2020).…”

Adsorption Capacity and Phosphate Removal Efficiency of Oyster Shells and its Implications to Chemistry Learning

“…Water quality degradation issue in ecosystems that support aquaculture has remained one of the main problems for the sector as it triggers and causes an increase in the concentration of phosphates and nitrates, which could lead to deleterious effects because studies found that when the concentration of these materials are beyond the recommended level can cause adverse effects on dissolved oxygen concentrations of the site, trophic state and ultimately the well-being of the fauna and flora of the site (UN Water, 2015). For example, Manila Bay was found to be unsuitable for fish culture, although its temperature, DO level, and pH were within the safe levels, because its Phosphate and nitrate contents are too high (1.02 mg/L -2.42 mg/L, and 0.90 mg/L -2.35 mg/L) (Baldoza et al, 2020).…”