This product is so easy to use. It literally clumps up the metal in the water and drops it to the bottom so it can be vacuumed out. My granddaughters no longer get green stripes in their beautiful blonde hair.4 th time we ordered. Good deal!This product works! I’ve used it for several years.We have really hard water and need this type of chemical for our pool each year. Metal Free is the easiest, cheapest additive that does the job in my opinion. You need to be sure that it will treat your issue and that it is not something else and you need to brush your pool.Being consistent each week, I have taken nearly all the stain out of my pool, which took about 5 weeks. I don't brush the pool everyday more like twice a week. (I have a vinyl liner.) When I started using Metal Free this year the staining in my pool was moderate heading towards bad, I had already used a Stain Remover, by Leslie's (very expensive) once earlier in the season. The stain remover works great but it has no lasting treatment, which I need.Metal Free does both the stain removing and lasting treatment, I use it exactly as the bottle says too. I will continue to use Metal Free from now on.Product arrive leaking even though it was sealed within a plastic bag.These two bottles of Metal Free were delivered quickly, and the packaging was secure. Last summer, I unknowingly used a shock containing copper. In September, my pool turned green. After much research and consultation, I bought and used this product in tandem with another metal-reducing agent. A capful of Metal Free each week helps reduce the copper present in my pool, and leads to a cleaner pool and, happily, less maintenance.I use to get big brown stains on my pool caused by to much metals in the water. This stuff has stopped thise stains for years. Just 2 cups per week in the pool and metal stains never developMy pool water turned green from minerals when we filled it up at the beginning of summer. I put the Natural Chemistry in as directed and my pool was blue again. One bottle on a 27' round pool. I usually have to get 2 or 3 bottles when I buy the metal out type product at Lowes or Walmart