The results showed that range of total organic matter in four stations from July to August were 8.7970 to 31.7983, 5.0072 to 16.4545, 6.8238 to 29.1338, 6.2413 to 14.9514 respectively. Koh loy were the range of total coliform bacteria and fecal coliform bacteria because there are residential, restaurant, boat dock, and the amount of organic material including the right amount to meet the high diversity index.