Best way to remove Favites from tank glass?

[ESH]

I will have to temporarily take my tank down (water damage to floors) and have a Favites thats had some decent growth across a bare bottom tank.
Whats the best way to remove it from the aquarium glass? Razor blade along the edges and try to pry it up? I realize it’ll break up, just trying to save as much as possible.

 

[KrisReef]

Sometimes these will lift off surprizingly easy from the glass, intact. I use a putty knife to slide under the edge to lift that off to start, and sometimes the entire chunk will slide and life off in one piece? Otherwise, scrape with the putty knife and take the frags to the LFS, hopefully not to many frags.