Water filter sand level sensor

An apparatus comprising:

• a sand level sensor positioned inside a water filter;
• an indicator positioned outside the water filter and connected to the sand level sensor and providing a visual or audible signal regarding a sand level in the water filter;
• the sand level sensor including an ultrasonic transducer transmitting ultrasonic energy bursts vertically down through the water filter to the sand level and determining a time difference between a transmitted and a reflected signal;
• the indicator turning on or off in response to the time difference between the transmitted and reflected signals from the ultrasonic transducer.

An apparatus comprising:

• a sand level sensor positioned inside a water filter and detecting if a sand level in the water filter is above or below a critical level;
• an indicator positioned outside the water filter and connected to the sand level sensor and providing a visual or audible signal regarding the sand level in the water filter;
• an electrical power source connected to and powering the sand level sensor and the indicator;
• and
• an actuation switch turning on and off the sand level sensor.