The objective of this research is to develop an IoT system to notify of the level of ammonia evaporating from water and send a notification to the Line Notification File. The water level is measured by using ultrasonic sensors. and display the values on the dashboard on the website For raising aquatic animals It is connected to the gas sensor system to receive the ammonia value. For controlling the environment in ponds where aquatic animals are raised. The website shows information about ammonia levels. which is important information for raising aquatic animals User can receive ammonia information. and receive notifications via Line (Line Notification) The system has a notification accuracy of more than 95% when the ammonia level in the pond exceeds the set value. which is an important factor for the growth of aquatic animals The system will record data for viewing in the past. This makes it possible to examine the pattern of changes in the ammonia effect in the water. By testing, preparing tools and setting up ammonia gas detection sensors. This experiment was performed more than 10 times to find discrepancies and conclusive results. To help farmers control ammonia levels to a level suitable for the growth of aquatic animals. The system will result in farmers reducing costs by up to 90% and having a better understanding of the use of IoT technology in raising aquatic animals.