Reverse Undergravel Filter

Conventional undergravel filters suck the water down through the gravel. This leads to solid waste collecting in the substrate.

A reverse undergravel filter on the other hand pushes the water from below. This means the substrate need not be turned over with a siphon to keep it functioning.

As a result there is less maintenance and the beneficial microbes in the gravel are not disturbed regularly. Maintaining these bacteria are essential for removing harmful compounds from fish waste.

This type of undergravel filter consists of slotted pipes laid at the bottom of the aquarium. Electrical conduit is frequently used because it is easy to cut with a hacksaw and provides a good with.

A pump draws water from the tank and pushes it through the piping. The water entering the pump should be drawn through a large sponge to stop fish losses and collect solids. Additionally the sponge will itself perform biological filtration in addition to the microbial activity in the gravel over the pipes.