Filtration is one of the most basic components of the aquarium ecosystem. As fish live in the aquarium, they produce waste. This waste is joined by other materials, such as leftover food, detritus shed by plants, and chemical and biological compounds created by the aquarium environment. In open water, these materials aren’t an issue because there’s so much space available. In an aquarium, even a large one, these can build up to to dangerous concentrations, threatening the wellbeing of the aquarium inhabitants.
Filtration helps to continually remove these materials from the aquarium. To start, there are three basic types of filtration, classified by the way they work:
Mechanical filtration— forces water through a medium in order to filter out particles above a certain size threshold.
Chemical filtration— uses chemical bonds to trap certain particles that stick to other particles types in the filter.
Biological filtration— happens naturally as certain organisms act on other compounds in your aquarium. Also commonly referred to as the nitrogen cycle, this involves fish waste being converted into ammonia, which is then turned into nitrites, which are then converted to nitrates, all via biological processes.
Next month, we’ll discuss the Pros and Cons of using specific types of filters for your aquarium, including sponge filters, undergravel filters, and more specialized filters such as protein skimmers.