Even though your artificial insemination tank may have provided years of trouble-free service, all units will eventually fail. To head off trouble, check the nitrogen level in your tank regularly.

The frequency of checking depends on the size of your tank. The larger the tank, the slower nitrogen evaporates from the refrigerator. For example, small tanks that must be refilled every four weeks require weekly checking, while tanks that are refilled every five to six months require checking every six weeks.

Use the following chart to determine the ideal nitrogen level, depending on how long it has been since your AI representative last refilled the tank. If your tank reads more than 2 centimeters below the ideal level, call your AI representative to check the tank.