Ultimate Easiest Aquarium Glass Scraper - Clean your glass in seconds
This scraper is probably my favorite thing in my fish room. I've tried every method to clean glass before realizing how great a sharp razorblade is. It's actually less likely to scratch glass than scrubbers, because scrubbers pick up sand and smash it against the glass.
This thing is wide enough that you can clean your entire tank's glass in seconds. The blades stay sharp for WEEKS, which means I can use this thing to clean all 50+ of my tanks in only a few minutes.
This scraper also includes extra razors that will last you literal years.
The "High Quality" option is reinforced and has a more grippy handle.
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Ultimate Easiest Aquarium Glass Scraper - Clean your glass in seconds