Well yeah if you use a little common sense and if it doesnt come off clean discontinue scraping it off. And there is a way to scrape glass with out scratching it. Take a razor and hold it at a 45D angle or less and push against the glass. If it doesnt come off clean them stop and i guess just leave it, or make a rock wall, moss wall, tall plants, or any other form as a background in the tank.
- depthC