| I do not believe the number of chambers necessarily matters, but the overall filter design does matter and that could influence the number of chambers. For example, I had a multi-chamber filter composed of: a net to capture leaves and large items, followed by large brushes, followed by smaller brushes, followed by Japanese blue matting, followed by sponges, followed by bioballs. That took 6 chambers. It is important to maintain high levels of dissolved oxygen to maximize nitrification. This can be done through pumping air into the system via airstones. In some filter designs, however, the water flows up through a media and then falls over a weir to the next chamber where it flows downward. These up/down flows expose the water to the atmosphere and allow some gas exchange. If the chambers are too large, the gas exchange is not optimized. So, in those types of filters, the chambers need to be smallish and you may need more than one chamber for a particular media.
To answer your question, it all depends on the filter design overall. As one of our occasional posters is fond of saying, "It's a system." |