Swimming pool salt causes stains

Almost daily we receive calls from distressed clients saying the following – “I got some cheap swimming pool salt from my local hardware store and now I’ve got these ugly brown stains in my pool”.  Often, this brown staining becomes evident within hours of adding the salt to the water. Remember, contaminated salt can also discolour the water and turn it brown almost instantly.  Many pool owners around the world face this issue.

Salt is salt, right?  So, what’s the difference between bad salt and good salt and why does it matter to your pool? Let’s find out.

Salt stain in pool?

Stains from salt are caused by the mineral contaminates contained within the salt precipitating onto the surface of your pool.  These salt stains are removed with our granular stain compound within a few weeks.  The best news is that this can be done without draining the pool or acid washing. So please feel free to call The Pool Stain Removers today.  Our salt stain removal kit has been used by more than 2,000 pool owners with great results.

Salt staining in swimming pool
This customer added a bag of cheap salt to the pool. When she checked the pool the following day this stripe of brown had embedded into the pool surface. This happened because the mineral contaminants bonded to the pool surface while the salt was dissolving.

Good pool salt vs. bad.  What’s the difference?

Because salt is a natural product, all pool salt has the same basic properties. However, the mineral, water, contaminate and metal content found in pool salt can vary significantly from brand to brand.  For this reason, the salt used in your pool has a significant impact on the total volume of minerals and metals that are dissolved into your pool water over time. These minerals will later discolour and stain your pool interior, particularly if your pool water balance is not maintained.

What makes staining from pool salt an issue is that pool water evaporates over time, but minerals and metals do not.  These minerals remain suspended in the pool water, even when the pool is topped up with fresh water. Over time, these minerals will precipitate or ‘plate out’ onto the surface of the pool.  When this happens a light brown film appears all over the pool surface that will not brush away.  Remember, quality salt will significantly slow down this mineral accumulation in your pool.  This is because there are less contaminates and minerals in good quality salt.  Therefore, it will also reduce the chances of visible staining in your pool.

Did you know that the average pool owner only spends around $120 per year on swimming pool salt?  It is unwise to cut corners by using cheap salt when the consequences can be so costly.

How can I recognize poor quality salt?

There are 5 things that typically characterize poor quality salt.  They are as follows –

  1. Crystal size is large
  2. Salt is discoloured
  3. It is slow to dissolve
  4. It turns the water murky 
  5. Salt leaves brown stains in your pool

If the salt brand you are currently using matches ANY of the attributes in the list above then we strongly suggest trying an alternative.

What does good quality salt look like?

There are five things that characterize good quality pool salt.  They are as follows –

  1. Crystals are very small
  2. Crystals are fast dissolving in water
  3. Salt bag shows a purity level of more than 99.5%
  4. Product is brilliant white in appearance
  5. Pool water feels soft and comfortable for swimmers

Good quality salt will cost a fortune, right?

Most pools consume around 10-12 bags of salt per year to maintain correct salt levels.  The cost difference between poor and high-quality salt is around $4 per 20kg bag.  So the $50 additional cost for quality salt is hardly a budget blowout for pool owners.  On the other hand, the cost of removing stains caused by poor quality salt can sometimes be over $1,200.00. From a financial perspective, cheap salt does not make any sense at all.

There are times when inexpensive brands sell reasonably high quality batches of salt.  However, less expensive brands need to source lower grade salt in order to meet the low prices some consumers demand.  Therefore, the chances of purchasing a contaminated batch of salt is generally higher with less expensive brands. Remember, high purity, fine salt is in demand in several industries and so it simply costs more to buy.

swimming pool salt grading
Although salt is a natural product, the variation in the level of contamination from one location to the next can be substantial. This means that those contaminates will bond to your pool surface as the salt dissolves.
Mineral salt stains on fibreglass pool
This pool owner left a bag of contaminated mineral salt on the steps of his pool to dissolve. The next morning he was stunned to see dark staining on the surface of his pool.
salt stain in swimming pool
Most commonly salt stains will leave a brown discoloration over the surface of the pool. This often slowly builds over time.

Swimming pool salt cost and qualities

Remember, salt is sold by weight not by volume.  This means that some low-cost brands will bulk buy moisture-rich low-quality salt at a low price in order to undercut their competitors.  From a price and visual perspective, this salt will seem perfectly fine.  However, moisture adds weight which means that if the salt moisture levels are high then you’re actually paying for water rather than salt! Therefore, the actual amount of pure salt you have in your salt bag will depend on the quality of the salt, not the total weight or size of the bag.

Although no brand or batch of salt is 100% pure and completely free of contaminates, high-quality brands generally have better quality control and accurate measures to monitor mineral content during selection and bagging.  These quality brands will often not purchase low-grade salt from the suppliers.

Remember, when quality salt is added correctly it saves you money over the life of your pool and will actually cost you less in the long term.

Do you have any comments or experiences with salt that you would like to share?  We look forward to hearing about them via the email address on our website.

salt stains in swimming pool
Our client in Melbourne, Australia placed a full bag of salt on the steps of their pool and left it to dissolve overnight. The next morning the steps and the entire pool had a horrible brown stain caused from contaminates within the salt.

Got salt staining?

Speak to a stain specialist today without cost or obligation.  We are happy to look at pictures and talk with you before we come out or send a kit. Please feel free to email pictures of your pool to info@thepoolstainremovers.com.au or call us.

Call now!Call now!

References

Colour, crystal size and purity – http://www.poolandspareview.com.au

Adding salt to your pool correctly – http://www.saltwaterpoolandspa.com

Long term benefits of using good quality salt – http://www.riverpoolsandspas.com

Salt graded by water content – http://www.saltcomindia.gov.in