For the hard to remove algae on aquarium glass (not for use on acrylic).
Step 1: What You Will Need
1. 3/8 in wood dowel (cut to appropriate length for your aquarium).
2. Single-edge razor blade.
3. Small machine screw.
4. Super glue.
Step 2: Saw 45 Degree Notch
Make notch only wide enough for the razor blade holder edge to fit snugly.
Step 3: Saw or Sand End Parallel to Notch
Step 4: Drill Pilot Hole for Machine Screw
Drill through to slot.
Step 5: Insert Blade and Tighten With Screw
Tape cutting edge while inserting and tightening.
Step 6: Add Super Glue to Underside of Blade Dowel Interface
Step 7: Watch Algae Disappear
Rinse and dry after use, especially if used in a saltwater aquarium.
You can prolong blade life by spraying with lacquer.
Blade can be easily replaced and re-glued.
Remember, DO NOT USE ON ACRYLIC.