Pool stains are not uncommon. Not all stains that occur in pools can be treated the same. The best way to treat a pool stain is to know what it is exactly that needs to be treated. There is no all –purpose pool stain treatment. Let’s look at the most common pool stains, what is causing them and how an experienced pool cleaner might treat it.
Blue/Green Stains
If you are seeing an accumulation of a blue/green substance this is copper. Copper stains are one of the most common stains seen in pools. Copper in pool water can come from algaecides, heat exchangers, older copper plumbing and a few other things.
Most cases of blue/green staining can be prevented by following proper dosing charts on algaecides maintaining a good pH level. Sometimes this doesn’t always happen and a pool cleaner can come in and treat with the proper granular stain remover or liquid remover made just for treating copper.
Purple Haze
If you are seeing a purple haze it’s copper cyanurate. When this happens you have a cyanuric acid level of around 100ppm and when it combines with copper in the pool it forms a purple precipitant on the surface of the pool, tile line, skimmers, and pool cleaner. The purple problem will not go away until the cyanuric acid level goes back down to around 50 ppm. Once this is lowered the staining usually goes away. Some spots may be stubborn and hang on these can be brushed away. Water should be tested after the levels are brought back down for remaining copper residual.
Brown Stains
The appearance of a brownish substance is caused by iron stains. Dissolved iron can make its way into a pool in many different ways. The most common ways iron gets into a pool include protective coating wearing away on the pool header exposing iron to the pool, erosion tablet feeder plumbed in without a proper check valve that erodes a header, fertilizers used in the yard by landscaping, and well water. Well water is probably the most common occurrence of iron in a pool.
Iron is removed from a pool the same way that copper is. It is also good to have the balance of the water checked and accurately pinpoint the source of the iron to reduce the chance of iron in the pool again. If you have iron from well water you will want to have your pool expert add a sequestering agent to the pool weekly.
Organic Stains
When leaves and other outdoor materials settle to the bottom of the pool or on winter covers in the off-season they can leave behind staining. Sometimes these stains go away very easily when the pool is balanced and shocked to get chlorine levels up. If stains still remain after balancing they can pretty easily be cleaned with citric or absorbic acid.
Galvanic Corrosion
This is more common in salt pools. It is an electrochemical process where one metal comes in contact with another and undergoes a corrosive attack. In salt pools with salt generators the cell is making chlorine. When metals are corroded they dissolve and reach saturation and stain the surface of the pool. It won’t corrode the salt cell though. This can be remedied with the addition of a sacrificial anode made of zinc. The zinc in a sense sacrifices itself to corrosion and the other metals are saved from corrosion.
There are many different types of staining in pools, but if you can identify what is causing the stain you can help aid a pool cleaning expert in knowing just what your pool needs to get back in shape. If you need a quality pool cleaning or stain removal EverClear Pool Service is happy to help with any pool care, repairs or maintenance needs.
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