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Remove Hard Water Stains or Scale from around Swimming Pool

Hard water stains and mineral deposits build up around the top of a swimming pool and it isn't that difficult to remove these stains if you tackle these head-on as soon as they occur.


If you have a swimming pool outdoor in the garden, you will have noticed that the mosaic tiles around the top of the pool tend to go hazy or white along the waterline. This whitish stain is caused by mineral deposits in your water and can be tricky to remove if left to build up over a long time.



Anyone who uses a borehole to fill up their swimming pool will definitely notice this scale build up along the waterline, since water from most boreholes contains quite a bit of minerals, particularly calcium or trace metals.

If not attended to on a regular basis, or before it builds up a thick layer of scale, it can be difficult but not impossible to remove. There are two many types of greyish-white build-up that can occur around the waterline of your pool, and both are treated in a similar method:





Removing calcium silicate or calcium carbonate

While both tend to look very similar in appearance, calcium silicate is significantly harder than calcium carbonate. Calcium silicate occurs when calcium carbonate has been left to harden, and it is necessary to treat this with a pumice stone. You can buy synthetic pumice stones at Clicks, crazy store or larger pharmacy chains like DisChem. Reasonably priced, you can pick up a decent sized pumice stone for around R10 each and they will last a long time.

Regular cleaning to prevent build-up is you best option and you can treat calcium carbonate muriatic acid, that can be bought at any Builders store or pool shop. Muriatic acid is what builders use to clean cement off bricks and paving and it dissolves calcium carbonate, making it easy to remove.

If you are unable to empty the pool, which makes sense when you consider how much water is in the pool, pour muriatic acid around the edge of the pool and leave overnight. You will notice that calcium carbonate fizzes when it comes into contact with muriatic acid. However, if no fizzing occurs it means that the calcium carbonate has hardened and become calcium silicate.

After treating with muriatic acid, use a pumice stone to remove any remaining residue.



Regular maintenance

After removing any scale build-up, keep mosaic tiles along the waterline clean on a regular basis with a scrubbing brush and vinegar. A regular brushing will prevent scale build-up and keep mosaic tiles around the waterline clean and shiny.



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