WISRD Research & Engineering Journal

Figure 8. Left: Fluval 407 canister filter. Right: Inside the canister is a side-by-side full-height mechanical filter (red plastic holding sponges) and a stack of plastic trays. The stack of plastic trays (Fig. 8, right and Fig. 9) in the Fluval 407 holds various types of filters. The top tray of the filter contains Black Diamond charcoal in mesh bags (Fig. 10), which filter undesirable chemicals and elements in the water of the aquarium. The next tray holds PhosGuard, used to remove phosphate and silicate from the water (Fig. 11); phosphates have been shown to increase algae levels in tanks. The 3rd tray is a biological filter (Fig. 12). In this filter, beneficial bacterial colonies propagate on high surface area ceramic rings. Some of these bacteria convert ammonia to nitrite and others convert nitrite to nitrate, both of which aid in maintaining proper levels of nitrogenous compounds in the tank. In the next filter levels are mechanical filters (Fig. 13), which remove particulate debris from the water. The tank water first goes through coarse, then medium-sized, then fine sponges. Polishing filters (Fig. 14) are added to one or more trays depending upon space. These polishing filters are made of polyester and remove the last of the fine impurities from the aquarium water column.

Figure 9. Stack of plastic trays holding different filtering mechanisms in the Fluval 407 canister filter.

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