How to fix visual problems with your spa water
Cloudy, milky, or greenish spa water can quickly spoil the enjoyment of bathing. These visual problems are often the result of chemical imbalances or ineffective filtration. Fortunately, there are solutions to remedy these issues and prevent them from recurring.
Start by testing your water
Filter problem
Appearance: The water does not clear up despite treatment or quickly becomes cloudy again.
Cartridge filter:
- Rinse the cartridge thoroughly.
- Clean the cartridge with filter cleaner.
- Replace the cartridge.
The essentials for fixing filter problems
Cloudy water
Cloudy water
Appearance: The water appears cloudy, milky, sometimes slightly gray or whitish.
Possible causes:
- Poor filtration (dirty or clogged filter)
- Chemical imbalance (pH, alkalinity, hardness)
- Suspended residues (sunscreen, pollen, organic debris)
- Lack of disinfectant
Solutions:
- Clean or replace the filter media (sand, cartridge, glass beads).
- Adjust the pH to between 7.2 and 7.6.
- Perform a shock treatment.
- Use a clarifier to collect fine particles.
The essentials for correcting cloudy water
Foamy water
Foamy water
Appearance:
Persistent white foam on the surface; fine bubbles that do not disappear quickly, sometimes with a slight oily film.
Possible causes:
- Surfactants (soap, shampoo, sunscreen, oils, detergent residue on swimsuits).
- Foaming anti-algae agents based on quaternary ammonium compounds (quats) or excessive use of additives.
- High TDS/organic load (“tired water”), lack of disinfectant.
- Insufficient filtration or clogged filter.
Solutions:
- Add an anti-foam agent to reduce foam.
- Clean/rinse the filter.
- Shock treat and replenish the disinfectant.
- Adjust the pH to 7.2–7.6 and partially replace the water if necessary.
Essentials for fixing stains on steps
Greenish water
Greenish or yellowish water
Appearance: The water appears light greenish or yellowish, even though it remains relatively clear.
Possible causes:
- Presence of oxidized metals (iron or copper)
- Reaction between chlorine and minerals
Solutions:
- Test for the presence of metals in the water.
- Add a metal sequestrant.
- Adjust the pH and carry out preventive treatment with a non-foaming algaecide.
Essentials for correcting greenish or yellowish water
Biofilm
Biofilm
Appearance: The water may appear slightly cloudy or show signs of viscosity (slightly oily or slippery texture) on walls and equipment. A viscous, sometimes colored deposit may be visible on surfaces.
Possible causes:
- Presence of biofilm, a layer of microorganisms (bacteria, algae) that builds up on spa surfaces, particularly in the pipes.
- Insufficient disinfectant or incorrectly adjusted pH, allowing bacteria to proliferate.
Solutions
- Remove headrests and any other removable accessories to allow for thorough cleaning.
- Replace the filter cartridge to prevent recontamination after treatment.
- Perform a shock treatment (superchlorination or other powerful disinfectant).
- Wait 24 hours.
- Run the spa jets for 20 minutes to circulate the treatment through the pipes.
- Wait another 24 hours.
- Use a specialized pipe cleaner (such as Whirl Pro or equivalent) to remove the biofilm.
- Drain your spa completely to remove contaminated water and biofilm residue.
- Clean and rinse the surfaces before refilling.
Essentials for correcting greenish or yellowish water
Expand your knowledge with our tips and advice
Are you unsure?
Visual problems can quickly worsen if they are not treated at the source. Testing the water in-store or using a reliable test kit will help you make the right diagnosis.
Consult our maintenance guide or come and meet one of our experts in-store to restore your water to a clear, healthy, and sparkling condition.
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