Fisheries are one of the most potential sources of foreign exchange for the country. Water quality in fish farming in freshwater ponds is a very important part because the growth and age of fish is strongly influenced by temperature and changes in dissolved oxygen levels, water pH and salt salinity. Fish farmed in freshwater ponds are thought to be more sensitive to sudden changes in water quality. In order to continue to produce good quality fish, a tool is needed to control the pH of the water in brackish water ponds where fish farming is carried out. A prototype of a brackish water pond with automatic sluice is designed that can maintain pH stability in a pond filled with brackish water. The floodgates are driven using a servo motor with an Esp 32 microcontroller. The system is able to accurately measure the pH of the water and the results of the measurements are sent to the database via Esp 32 and displayed via a web server. When the pH value in a brackish water pool is less than 7, the floodgates containing salt water will open automatically to stabilize the pH in the brackish water pool. However, if the pH value in the brackish water pool is 8, the door containing fresh water will open automatically.Keywords: Water, Esp 32, fish, pond, brackis
