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Dimension: 8x4.5cm/3.2” x1.8”, the inside hole diameter is 2cm/0.8”; for a snug fit, check the size you need carefully before placing an order. The sponge's inner diameter accommodates filter intake within 0.8-1 inches (20–25.4 mm) due to its elastic properties.
Lifesaver: Keeps baby fish, shrimp, and snails from getting sucked into hob filters, power heads or canister filters by simply putting a pc of this pre-filter sponge over the intake.
Improve Filtration: Does a good job in catching flake fish foods, plants and any other large particles floating in the water keeping the tank cleaner and last longer between cleanings.
Maintenance: Rinse the sponge roll periodically based on the bio load of your aquarium tank. The material holds up well to being rinsed and reused and allows great water flow.
Includes: 6 pcs of pre-filter sponge (Note: The hole doesn't go all the way through the sponge. They come flattened in a vacuum bag; just unpack and rinse them and these sponge filters will puff up to normal shape and size.)

Product description

Key Feature:

The filter intake sponge cover is a great baby fish saver to protect your lovely little aquarium critters from being sucked in

This pre-filter sponge also can be used to dampen the outflow and make the water more stable for your betta.

The cylinder sponge foam prolongs the life of the pump unit and boosts mechanical filtration by keeping solid waste from getting into filters.

This prefilter sponge provide both mechanical and bio filtration

It is recommended to rinse the sponge roll periodically based on the bio load of your aquarium tank, as it will get dirty over the time and may restrict the water flow of the filter.

Package includes:

6 pcs of prefilter sponge