Are Sponge Filters Good Filters?

So, why are the vast majority of new fish keepers kept in the dark? If I were to blame of group of people, I would blame the big pet store chains who don’t offer sponge filters and try to promote their other more expensive filters. They also upsell these expensive filters by selling “refillable cartridges” that need to be replaced monthly. In other words, sponge filters don’t make them a whole lot of money compared to other filters.

This type of filter provides two types of filtration. The mechanical filtration comes into play when debris gets lodged into the sponge. The second form of filtration comes into play when the sponge starts to grow an active bacteria colony on the sponge which provides a huge surface area for the bacteria to grow on.