Corner filters are ideal for medium-sized aquariums. They are one of the most effective and oldest styles of filters. They help optimise the water quality in your tank, which contributes to the overall health of your plants and fish. You can use an air-driven filter to keep the water clean and promote the overall health and wellness of fish in your aquarium. The rising bubbles in a long, narrow tunnel create a vacuum-like suction at the bottom, which pulls water through the filter. This filter is suitable for small tanks and aquariums, increasing oxygen solubility in water. You will need airline tubing and an air pump to use this filter. It is important to note that this filter has a large base.