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Tinted Water and Stains
If minerals are present in the pool water, they can cause the pool water to turn green, brown, yellow, and even purple. The water would look clear but discolored. It can be very difficult to distinguish between green water caused by green algae and green water caused by a mineral problem. A telltale sign of a mineral problem is the discoloring of the pool water shortly after shocking the pool. If this occurs, you will need to add a mineral sequester to the pool. Exactly how much is a guess. We have seen cases where one bottle has solved the problem, and others where multiple bottles were needed. Mineral problems are a tough nut to crack and the pool industry is just now trying to get a handle on it. Stains on the vinyl liner are also treated by adding a mineral sequester. Persistent stains might need to be treated with an "on contact" product that must be applied directly to the stained area of the pool. If the stain is on the bottom of the pool, applying the product directly on the stain can be tricky, but possible.