A long-time neighbor, who I'd never met before covid, mentioned to me that her husband was home washing their trex deck while we were out walking. I responded that we also had a trex deck, but a very old one. We got to talking about trex and how we maintain it: I've always used power washing and diluted bleach over the last 25 years. She told me that's exactly what the recommend I NOT do! So I asked what she used and she threw out a name I'd never heard of before. I tried to Google it when we got home but my search hit a dead end. Later that week I asked her to write down or take a picture of the product she uses for the deck. It was Corto-Clean. At first I thought it was expensive but I decided to buy 2 bags of the product to give it a try. If it didn't work, I was out $90 but if I liked it, I probably wouldn't need to use as much going forward. Well she stopped by while I was cleaning the lower deck and I was so thrilled with the transformation even after only one application. The second application the next day made the deck look almost new again! The other deck, which is now a porch, had a very old stain from where we used to have our grill. While it didn't remove the stain entirely, it made a huge difference. I'm confident that I can make it nearly disappear with future applications. Only a small amount remains of the 2 bags I bought. Rugs & furniture cover my problem areas but I definitely will be cleaning with Corto-Clean at least annually, if not again in the Fall. I'm so glad she recommended your product & I'm thrilled with the results. So is my husband! Respectfully Rose Weed