1.The fish tank thermometer uses an LED screen to display the temperature. The LED provides a wide viewing angle and saturated colors, making it easy to read the data both during the day and at night. It is also environmentally friendly and energy-saving. 2.The thermometer for the water tank of the aquarium only needs to be peeled off and stuck below the water level on the outside of the tank. This glass container thermometer has a reading range of 0-140°F and is accurate to 0.9 degrees Fahrenheit. With a refresh rate of up to 5 seconds, it allows for faster detection of temperature changes with the naked eye.