Keep your tank clean and your glass safe with Continuum Continuum AquaBlade hand-held glass scrapers are the safest option for maintaining your aquarium glass. The continuum scraper can help you prevent scratches in your glass by allowing for more control over where the blade is and what it comes into contact with. With strong, 316 Stainless steel, blades, rest assured that your film algae will be gone with one swipe of your scraper blade.