Product review (3 stars): It works fine if the instructions are being followed!
The filter will work fine and last long time only if special care of the operation of the humidifier is in order. It has to run constantly, refilled daily and never let run dry. The tray and the canister have to be clean twice a week. The use of Bacteriostatic Treatment can help to make the operation optimum. By the way the filter use to be $6.99 now is $14.75.