PENGARUH PEMBERIAN PHOTO SYNTETIC BACTERIA TERHADAP PERTUMBUHAN DAN KUALITAS AIR BUDIDAYA UDANG VANAMEI (Litopenaeus vannamei) SISTEM INTENSIF

Vannamei shrimp (Litopenaeus vannamei) is one of the leading commodities in fisheries. Vannamei shrimp is also considered an introduced species that is resistant to diseases and grows rapidly. The cultivation of vannamei shrimp requires attention to maintaining water quality parameters such as salinity, pH, temperature, and brightness. Water quality plays an important role in the growth of vannamei shrimp. Photosynthetic bacteria are bacteria that decompose the bottom of water bodies using sunlight to produce energy. Photosynthetic bacteria produce a purple-colored bacterium called Rhodobacter sp. Photosynthetic bacteria are found in places such as rice fields, sewers, soil, riverbeds, beaches, and waste disposal plants. The absorption process of these bacteria uses bacteriochlorophyll compounds to capture sunlight, and their photosynthesis occurs anaerobically (without oxygen/does not produce oxygen). There are four groups of bacteria that perform anaerobic photosynthesis: green sulfur bacteria, acidobacteria, red and green phototrophic bacteria, purple bacteria, and heliobacteria. Photosynthetic bacteria play an important role in agriculture, livestock farming, aquatic environments, pharmacy, and ecology to control bottom waste. The purpose of this research is to provide information about photosynthetic bacteria for farmers, which is useful in controlling environmental pollution in pond bottoms and water quality. The research method used is descriptive. The results show that the application of Photosynthetic Bacteria at different doses resulted in a growth rate value of 0.180 grams/day and an FCR value of 1.154. The effect of Photosynthetic Bacteria on the water quality of vannamei shrimp cultivation is quite optimal, with salinity ranging from 16-21 ppt, pH from 7.02-8.15, temperature from 26-31°C, and brightness from 26-67 cm.