Note: This is attached to the surface of the fish tank, not in water, the temperature measuring probe is attached to the wall of the fish tank, simple and pureSeveral layers of glass,Basically, the temperature is accurate, but each thermometer manufacturer is different, and the temperature measurement implementation standards will be deviated, but the approximate temperature is correct, which can help you understand the approximate temperature of the fish tank.If your requirements are very harsh temperature display, please be careful, because in theory, this can only be done by using precision scientific experimental instruments.