Best product to scrape algae with no scratches?

[Noahp]

Hey all first off some details I have a glass tank and have been using a metal algae scraper, the issue is I keep getting scratches where I scrape! I tyed an acrylicblade and it won't clean the harder algae. So is there any blade les likely to scratch but will still get the job done?

 

[saltwater bob]

I use a Mag Float with an attachment called Easy Blade. Works great. Here is link to it.

Easy Blade Scraper Attachment for Aquarium Algae Magnet Cleaner