Penn Plax Wizard Algae Scrubber Pad for Acrylic or Plastic Aquariums helps with the removal of waste from your aquarium. Safe to use on both freshwater and saltwater acrylic or plastic aquariums to aid in the removal of algae and hard water deposits. Always rinse with tap water before use (never use dry) and avoid using heavy pressure which may result in scratches on your tank.
Instructions: Always rinse with tap water before and after use, never use dry. Avoid getting sand or gravel on the pad and avoid using excessive pressure; these may cause scratching.