top of page

Help! What Are These Black Spots in My Pool?

As the weather warms up and pool season approaches, there's nothing quite like the excitement of diving into crystal-clear waters. However, this excitement can quickly turn to dismay when you spot mysterious black spots lurking on the surface of your pool. Before you start to panic, let's dive into what these black spots could be and how you can tackle them head-on.


Black Spot Algae:

Black Spot Algae

One of the most common culprits behind those pesky black spots is black spot algae. This stubborn algae species can take hold in your pool, especially in areas with poor circulation or inadequate sanitation.


Black spot algae thrives in shady areas and can be quite resistant to standard pool treatments.



Rust Spots:

Rust Spots in Pool

Another possibility is rust spots, which can occur due to metal contaminants in the water or from metal components within the pool itself corroding over time.


These spots can appear black or dark brown and may spread if left untreated.




Osmosis or Mineral Deposits from Salts/Algaecides

Osmosis in Pool

Black spot algae rarely forms in fibre glass pools due to the smooth surface that makes it difficult for algae to attach and penetrate.


Unlike pebble pools where black spot algae can embed itself deeply, fibreglass surfaces are not conducive to its growth. While some spots may resemble black spot algae, they are often mineral or metal deposits shaped like black dots.


These black spots in fibreglass pools are typically caused by osmosis or deposits from pool salts or algaecides. Fortunately, these spots usually vanish within a few days with our stain treatment. It's essential to note that using an algaecide meant for black spot algae won't eliminate these spots and might exacerbate the issue. Treating them with algaecide could actually worsen their appearance.


So... how do you tackle these black spots and restore your pool to its former glory?

This is where Pool Wizard comes to the rescue. Pool Wizard specialises in diagnosing and treating various pool issues, including black spots. Their team of experts will conduct a thorough assessment of your pool to determine the root cause of the problem. Once the culprit has been identified, they'll tailor their approach accordingly, as each type of spot requires a different treatment.


For black spot algae, we recommend a combination of shock treatments, brushing, and the use of algaecides specifically formulated to combat black algae. Rust spots may require the application of rust stain removers or sequestering agents to prevent further oxidation. In the case of osmosis or mineral deposits in fibreglass pools, we advise on solutions to restore the pool's surface and prevent future mineral leaching.


Our expertise doesn't stop here though! We'll also provide guidance on how to prevent black spots from reoccurring in the future. This might include regular maintenance routines, proper water balance management, and ensuring adequate circulation and filtration.


So, if you find yourself faced with mysterious black spots in your pool, don't despair. With the help of Pool Wizard, you can bid farewell to those unsightly blemishes and get back to enjoying your pool oasis in no time.

Sliding into Pool
"Pool Wizard has transformed my pool from green to crystal clear. They knew how to fix the problem first go without the run around of other companies and actually turned up when they said they would. Being a smaller business I felt I could trust their advice without feeling like I was being upsold."

Jordan, Stretton QLD

bottom of page