Pool Stains: What Are They and How to Get Rid of Them

A pool is a big investment, so it’s only natural that you’ll want yours to look its best. However, if unsightly stains mark your pool’s surface, this can make your next swim significantly less relaxing and change the overall aesthetic of your pool. 

Sometimes, pool stains just can’t be avoided and even the most vigilant pool owners among us aren’t immune to this annoyance. But what causes pool stains? And how can you remove them? The team here at Miller Pools is here to talk you through this.

What causes pool stains?

Pool stains can be caused by a number of different factors and identifying what has created the stain is key for deciding how best to remove it. Common factors include:

• Organic matter: You’re probably familiar with the annoyance of finding leaves, twigs, and other organic matter floating around your pool; that’s why you should be regularly skimming your pool to remove any debris. If leaves are left to decompose, this can leave behind unsightly green-brown stains. If you have fruit bushes growing near your pool, you should also be on the lookout for any stray berries as these can create bright red-blue stains if left.

• Metals: An excess of metal in your pool water – whether that’s in the water supply itself or if it has leached into the water via corroding pool equipment – can create stubborn stains. You can usually identify which metal has caused the issue by the color of the stain: manganese creates purple-black stains, copper produces blue-green stains, and rusting iron components result in red-brown stains.

• Excess calcium: If you’ve noticed white, chalky deposits on your pool walls or if the surface itself feels rough to the touch, this is likely caused by a buildup of calcium as a result of a chemical imbalance.

• Poor maintenance: Failure to regularly clean and maintain your pool can contribute to pool stains developing, and many of the factors that we’ve covered above are exacerbated by neglecting proper upkeep.

How to remove pool stains

The best method for removing a pool stain depends entirely on how the stain got there in the first place. However, organic stains are typically much easier to remove than metal ones. 

One easy way to test whether the stain is organic is to apply a small amount of chlorine to the stain; while metal stains won’t react to chlorine at all, organic stains will often lighten or disappear.

Removing an organic pool stain is simple enough and involves some elbow grease and chemicals. Simply test and balance your pool water – you can enlist the help of a professional to ensure this is done properly – and then add some shock overnight to increase the levels of chlorine. Then, brush the pool walls, paying particular attention to any stained areas, and run the pump for a few hours before brushing the pool again. If the stains are especially stubborn, repeat this process until you notice a difference.

Metal stains can be a little trickier to remove, so the easiest way to do this is to get in touch with a pool expert like Miller Pools. We can test your pool water to determine what type of metal has caused the issue and help remove/repair the stains. 

Depending on the severity of the stains, calcium stains can usually be removed with either a pumice stone or a commercial stain remover; check out our previous article on this topic for more information.

How to prevent pool stains

Quite simply, the best way to prevent pool stains from forming in the first place is by implementing a consistent pool maintenance routine that includes:

• Routine water testing 
• Regular skimming and cleaning
• Chemical balancing 
• Equipment inspections, repairs, and maintenance

Our weekly cleaning and maintenance department can help prevent stains and ensure the longevity of your water chemistry, stress free!

If you’ve noticed stains on your pool walls, don’t just ignore them – get in touch with the professionals here at Miller Pools. For more than 30 years, we’ve been supporting pool owners throughout Humble, Atascocita, Pasadena, Galveston and the wider Texas region with our comprehensive pool maintenance service. Available on an occasional or weekly basis, we’ll work around your schedule and make pool care a breeze – contact us today to arrange an appointment.