The pre-filter or intake sponge is a simple foam cylinder that is designed to slip over the intake tube of hang-on-back (HOB) and canister filters. The filter intake tube often has large openings that allow sizable objects to get sucked up by the filter, potentially ruining the motor, so use a pre-filter sponge to help prevent baby fish, dwarf shrimp, little snails, plant leaves, fish food, and other debris from entering the filter. (depending on filters suction, and size of animal, tiny fry/shrimp/snails can still get through in some cases)
An intake sponge also provides valuable surface area to grow beneficial bacteria, which purify waste chemicals in the water and make it safe for your fish to live in. Finally, it adds mechanical filtration that extends the life and efficiency of your filter media.
- Increases Filter Capacity
- Prevents Small Fish and Debris from Getting Sucked Up
- Uses Coarse Foam to Extend Time Between Cleaning
Intake hole: 1.25 inches
Diameter: 3.5 inches
Length: 5.5 inches
Pore Size: approximately 20–25 ppi
Cleaning Instructions: Use a large fish bag, Ziplock bag, or pitcher to put around the sponge while inside of the aquarium. Lift the water and sponge out to catch the majority of debris that comes off during removal. Next, squeeze the sponge inside the container of aquarium water. Discard the dirty water, get more water from the aquarium, and repeat until sponge filter is mostly free of debris. (If you're only using the pre filter sponge as a mechanical filter, you can also rinse it at the sink.) Reinstall the sponge and wait for a couple hours for the water to clear back up from the debris released when removing and reinstalling.