Anything that is larger in size than a molecule of water is removed by a ceramic water filter. Water is introduced on one of the filter's sides, as is the case in many other methods of filtration. Besides presenting a very effective alternative, ceramic water filters present one that is relatively low-cost. These filters make use of ceramic material that has small pores that help to filter out the contaminants. When ceramic water filters are made use of, bacteria, debris and dirt can be cleansed out of the water.

On the side of the filter on which clean water is collected, some of the smaller contaminants also accumulate, along with the water. To protect the filter's body against algae and mold growth and to put bacteria out of action, colloidal silver is often used to treat ceramic water filters. Candle type and pot type are the ceramic water filters of the commonest kind. The health of the users, however, may be impacted negatively on account of the by-products that may originate from the media impregnated with silver.

Many non-governmental organizations have undertaken initiatives for drinking water development in third world countries and make use of ceramic water filters that are constructed in the form of clay pots, for the purpose. The ceramic water filter is porous and a receptacle made of plastic or ceramic material is placed below it, generally. So that water can be dispensed from it, the receptacle is generally attached with a tap.

Soap and hot water are often used for cleaning ceramic water filters. Accumulation of contaminants that are too large to pass through the pores of the filter necessitates the cleaning. The contaminants that are accumulated in the upper part of the filter can be rinsed out with water, for the purpose of cleaning, in addition to a soft brush being used to clean the upper half of the ceramic water filter.

To clean the accumulated material from the filter and to flush the pores of the contaminants, clean water is often made to flow in the reverse direction, as against the one in which it flows usually. This is a method often applied for cleaning of in-line filters that source water from the household's plumbing, which is meant for drinking, besides ceramic water filters that are based upon manual pumping and are portable.

For the majority of ceramic water filter systems, the risks that need to be watched out for include cracks of the hairline kind and cross-contamination. In the case of accidental dropping of the water filter and, specifically, due to the brittleness of the materials used to produce ceramic water filters, cracks that are difficult to detect may develop and these may let contaminants to pass through. If the side that is meant to be clean comes into contact with unclean cloths, hands or water, the effectiveness of the filter can suffer serious negative impact. Before safe use of the ceramic water filter can be made again, in such instances, the clean side has to be sterilized properly.

The relatively lower yield of filtered water that is obtained from a ceramic water filter, as compared to some other kind of water filtration systems, can be another area of concern. The amount of water that is worthy of being drunk, produced by a typical ceramic water filter within an hour, hardly exceeds one or two liters. In countries where abundant use is made of water, this can be a problem, even as it may not be so in the developing countries, where conservation is stressed upon.

Some ceramic water filters can even cleanse harmful chemicals like chlorine, through the utilization of substances such as active carbon that can absorb such contaminants. The contaminants can, however, cause the carbon to get clogged, thus necessitating the replacement of the filters at regular intervals of time. Metal strainers are also made use of, in more advanced models of ceramic water filters. The advanced versions are often able to filter more water and in relatively shorter periods of time.