The Marina Aqua Minder has been designed to provide aquarium owners with an accurate and reliable aquarium monitoring system. The Marina Aqua-Minder constantly displays the aquarium temperature in either Celsius or Fahrenheit. It features an alarm setting for the aquarium high/low temperature. The alarm will sound and flash if the water temperature falls outside the chosen range. Programmable features include:- Water change interval schedule, Filter maintenance schedule System check schedule.