The Seapora Digital Thermometer is a professional digital thermometer that is perfect for hydroponic systems, aquariums, and reptile terrariums. With an easy-to-use selectable fahrenheit/celsius switch, this thermometer can accurately measure air and water temperatures up to +/- one degree. The large easy-to-read display makes it easy to keep track of your temperature, and the five second response time ensures that you will always have access to the most up-to-date temperature information.