Final answer:
The material that water passes through in a conventional filtration process is known as filter media, which may include sand, gravel, and charcoal to remove various contaminants.
Step-by-step explanation:
The material that water passes through in a conventional filtration process is known as filter media. This media can consist of various substances, including artificial membranes, sand, gravel, charcoal, and more technologically advanced systems. During the filtration stage, the clear water on top of the sedimentation tank flows through layers of sand, gravel, and charcoal. These different layers capture dissolved particles such as dust, parasites, bacteria, viruses, and chemicals, making the water cleaner and safer for use.
The type of filtration system selected depends on the desired filtering speed and how clean the water needs to be. The filter media not only removes solids like bacteria and dust but can also reduce turbidity, color, odors, and the amount of iron content. For even finer filtration, the water may be passed additionally through a carbon filter, such as charcoal, to remove organic particles.