Characterization of Vannamei Aquaculture Systems in Gerokgak, Bali: Water Management, Feeding, and Waste Handling

Vannamei shrimp (Litopenaeus vannamei) farming in coastal Bali has expanded rapidly, yet concerns remain about environmental impacts and management practices. This study aimed to evaluate the current practices of semi-intensive vannamei shrimp farming in Gerokgak, Buleleng Regency, focusing on infrastructure, water management, feeding strategies, and waste handling. Data were collected through field observations and semi-structured interviews with 10 small- to medium-scale farmers and 2 tourism stakeholders. The results show that farmers use HDPE-lined ponds and mix seawater with bore well water to maintain optimal salinity levels (~30 ppt). Water quality is monitored daily, including temperature (28–30 °C), pH (7.5–8.5), and dissolved oxygen (>5 mg/L), with aerators used to maintain stable conditions. Feeding is conducted manually 10 times a day based on check tray observation, helping maintain feed conversion efficiency and minimize organic waste. None of the farms had full-scale wastewater treatment facilities. Effluent is typically discharged through sedimentation ponds into open drains leading to coastal waters, with limited nutrient removal. Although no acute environmental damage was observed, stakeholders noted discoloration and odor in discharge channels near tourist zones. These findings underscore the need for integrated waste management solutions—such as constructed wetlands or communal treatment systems—and stricter enforcement of discharge regulations to support sustainable aquaculture in sensitive coastal regions. Keywords: Litopenaeus vannamei, semi-intensive farming, water quality, waste discharge, Gerokgak, Bali, coastal sustainability.