For aquarium hobbyists, this is a simple but useful product: a 2-pack of coarse pre-filter sponges from Turtle Clean (model 511). You slide these sponges over the intake tube of your aquarium filter. Their job is to act as a first line of defense, catching larger debris like plant matter, fish waste, or leftover food before it gets sucked into the main filter compartment. This helps keep your main filter media cleaner for longer and provides extra surface area for beneficial bacteria to grow (which is good for your tank's biological filtration). They're made of a durable, coarse foam. When they get dirty, you just rinse them out in some old tank water during a water change and put them back. It's a cheap and effective way to boost your filter's efficiency and protect your impeller from getting clogged. A staple item for many fish keepers.
