Every month or two? Holy crap what am I doing right? I get a full year out of mine. Each week I'll clean the glass once with just the mag float and then once a month I'll attach the blade to get rid of the coraline algae that has started to build up. Afterwards I'll give it a quick rinse with in freshwater to lessen the corrosion. That being said, I probably only use it about 12 times on my 120gal before replacing it with a new blade.

I like my blades super duper sharp, an oxymoron when I buy the cheapest ones haha. When I'm masking vinyl off for a client I go through way more scalpels than needed lol any resistance it's a new blade, I carried the habit over to scraping my tank of yuckies!

i could not live with out mine.fast and easy