Aquarium Pre-Filter Sponge and Protective Inlets - Pre-filter sponge for aquarium: provides a first line of mechanical filtration at the intake, preventing small fish and shrimp from being sucked into the filter and reducing debris reaching the main filtration. - Cotton wool pore media for nitrification: designed with a cotton-wool pore structure to support nitrification by offering surface area for beneficial bacteria, helping maintain water quality. - Water inlet protective cover: guards water inlets to prevent small fish and shrimp from being drawn in and helps isolate contaminants before they enter the filtration system. - Anti shrimp mesh cover and filter sleeve: adds extra protection for tiny tank inhabitants and prevents shrimp from entering the intake or getting trapped in the filter area. - Retains small fish and shrimp: captures and holds small fish and shrimp to prevent loss during maintenance or filter servicing. Use scenarios - New tank setup or fry/shrimp introduction: install to prevent accidental suction and support early filtration without harming inhabitants. - During filter cleaning or water changes: keep covers in place to minimize fish/shrimp loss and protect the intake. - Nano tanks or shrimp tanks with tiny inhabitants: provides protective intake protection while supporting basic nitrification for stable water conditions.