AquaBlade Replacement Blades for acrylic aquariums. A direct replacement for Continuum AquaBlade Scrapers. Designed just for acrylic aquariums, these blades are made of a self-lubricating plastic that is actually softer than acrylic but strong enough to remove stubborn coralline algae! Available in: 1-Pack, 2-Pack, 3-Pack. AquaBlade-P replacement blades were custom designed just for cleaning acrylic aquariums. Continuum Aquatics uses a special self-lubricating plastic that is softer than acrylic and will not scratch! Changing the blades out only takes a few seconds and there is nothing better than a fresh new blade for cleaning stubborn coralline algae or other deposits that may have formed on your glass.