Pond Paint is a non-toxic paint on the membrane for waterproofing concrete ponds. As well as waterproofing the pond, it will also stop lime from the concrete leaching into the water. Lime is highly Alkaline so raises the pH level, which can be harmful to fish and adds to algae problems. Make sure the pond is thoroughly cleaned and dried prior to using Pond Paint. 1.5 - 2.5m2 per Litre (approx.) In most cases, one coat is enough.