A sump filter is a type of filtration system commonly used in aquariums and ponds to maintain water quality. It works by collecting water from the tank or pond, filtering out debris and impurities, and then returning the clean water back into the environment. This process helps to keep the aquatic ecosystem healthy by removing harmful substances. Sump filters typically consist of several compartments that house different types of filtration media, such as mechanical, biological, and chemical filters. The mechanical filter removes larger particles, while the biological filter promotes beneficial bacteria that break down waste. Chemical filters can remove toxins and odors, ensuring a balanced and clean aquatic habitat.