I avoid letting my razor blade touch water as much as possible. The only moisture my razor really gets exposed to is the shaving lather on my face. After shaving, I carefully wipe my blade down with a couple of squares of toilet paper and store in the closet. Any traces of soap (which would be small) is low in acidity and protect the blade until next time. While shaving, I used to use a hand towel to wipe the lather off but now I use a foam beer cooler. Since they're cheap, I don't mind if they get cut up. When you 're ready just run the holder under warm water to clean it out.
Ernest