My 90 gallon acrylic tank also sits on a wooden platform, homemade. I have one scratch I haven't bothered with because it's very hard to see. It was my fault, I used a Tunze acrylic scraper. I seemed ok until I started using it, I soon found out that it simply didn't work well as advertised. Or operator error. I now use generic Mr. Clean erasers they work great on the acrylic.