Review on 12-Pack Replacement Charcoal Water Filters for Mr. Coffee Makers by NISPIRA by Stacey Littlejohn

Aquarium owners have long used activated carbon filters to improve water quality. The charcoal removes many of the dissolved chemicals in the water, leaving the bubble tank odorless. In a coffee maker, water is heated and forced to drip or spray onto the coffee grounds in the filter basket. These activated carbon filters are located at the top of the filter basket, so the water has to flow through the activated carbon and the water is cleaned before it reaches the bottom. Depending on what's in the water you're using (chlorine, fluoride, or other dissolved chemicals), these filters can greatly improve the flavor of your coffee. Just like in an aquarium, charcoal will need to be replaced sooner or later. They are designed for a month, but you can change them more or less depending on your taste and the amount of coffee you have.