Philippine Journal of Science
154 No. 1: 135-147, February 2025
ISSN 0031 – 7683
Date Received: 06 Sep 2024

France Guillian B. Rapiz, Ricksterlie C. Verzosa, Phoebe Nemenzo-Calica, and Misael B. Clapano

Litopenaeus vannamei requires a specific range of water quality parameters for optimal growth and health. Monitoring these parameters, as water enters (inlet) and exits (outlet) the shrimp ponds and throughout the canal system, is crucial in optimizing shrimp production, nutrient management, disease prevention, environmental protection, and compliance with regulatory standards. This study aimed to analyze water quality parameters at three different sites in Barangay Dahican, City of Mati, Davao Oriental, the Philippines, where all shrimp ponds in the area are located. Sampling stations were established at the inlet, canal, and outlet of each site, with sampling conducted in February and March to assess residual impacts of pond operations, assuming that most residues would be flushed out by March, leading to improved water quality. Assessed water quality parameters assessed included temperature, pH, salinity, dissolved oxygen (DO), chemical oxygen demand (COD), total suspended solids (TSS), ammonia, nitrite, nitrate, phosphorus, and alkalinity. Statistical analyses were performed. Results revealed that the temperature (26–28 ºC), pH (7.5–8.0), salinity (26–37 ppt), DO (3.5–6.4 mg/L), TSS (8–29 mg/L), ammonia (< 0.007 mg/L), nitrite (< 0.055 mg/L), nitrate (1.73–2.36 mg/L), phosphorus (< 0.12 mg/L), and alkalinity (129–187 mg/L) had values that fall within the safe, recommended and optimal range (with insignificant deviations) for L. vannamei ponds except for COD, which was substantially high (1,383–1,805 mg/L), comparable to domestic wastewater, and beyond the safe limit set by the Philippine regulatory standards for shrimp pond effluents (300 mg/L). It is recommended to reduce COD levels through efficient water quality management and treat effluents before discharge. Regular monitoring and management of water quality in shrimp ponds must be done to maintain the optimal conditions of the water quality parameters, thus improving the growth and production of L. vannamei and ensuring that the effluents are safe and non-hazardous to the environment.