Will a metal blade scraper scratch the back wall of a BC?

[OARrocks]

I used the scraper on my old glass 55g for getting off corraline and other junk but i am unsure of whether it will scratch the back wall.

Corraline is starting to form as my tank is only a month and a half but the main stuff i want to get off is this green encrusting algea that takes on the same shape and form as corraline. its hard like corraline and spreads just like it. i got a lot of it in my old 55 and since im using the same rock from that tank its starting in this tank.

any ideas?
thanks

[MikePowell]

yes but hold the razor and move it in the opposite direction. like if you make an acute angle and obtuse angle move he razor toward the acute and so that you move it away from the sharp side.