Pre-filtration: This is the first stage of water filtration and involves removing large particles, such as sediment, from the water. It can be done through a variety of methods, including straining or settling tanks. 2. Filtration: The second stage involves passing the pre-filtered water through a filter to remove smaller particles and contaminants that may have been missed in the pre-filtration process. This can include carbon filters, reverse osmosis systems, ultrafiltration membranes and more. 3. Post-treatment: The final step in water filtration is post-treatment which includes disinfection with ultraviolet light or chlorine to kill any remaining bacteria or viruses present in the filtered water before it is safe for consumption.