| Muraitic acid will do those things if left here, but if rinsed and dried thoroughly then sealed properly, it won't be there any more. At Home Depot both Lanco and Crossco have products for waterproofing that will work well on ponds. I believe they are acrylic base not concrete based. I think they run about $50 for a 5 gallon can. Next time I am there I will grab the specific names of them. |