How to solve visual problems with pool water
Cloudy, milky or greenish pool water can quickly spoil the pleasure of swimming. These visual problems often reflect chemical imbalances, inefficient filtration or the presence of algae. Fortunately, solutions exist to remedy these problems and prevent their recurrence.
Start by testing your water
Floating particles
Cloudy water
Filter problem
Appearance: Water does not clear up despite treatment, or quickly becomes cloudy again.
Cartridge filter :
- Rinse cartridge thoroughly
- Clean cartridge with Filter Cleaner
- Replace cartridge
Sand filter:
- Backwash or deep clean the filter
- Clean the sand
- Replace the sand or filter media
The essentials for correcting filter problems
Eau brouillée
Cloudy water
Appearance: The water appears cloudy, milky, sometimes slightly gray or whitish.
Possible causes :
- Poor filtration (dirty or saturated filter)
- Chemical imbalance (pH, alkalinity, hardness)
- Suspended residue (sunscreen, pollen, organic debris)
- Lack of disinfectant
Solutions:
- Clean or replace filter media (sand, cartridge, glass beads)
- Adjust pH to between 7.2 and 7.6
- Use a shock treatment
- Use a clarifier to consolidate fine particles
The essentials for correcting cloudy water
Taches dans les marches
Stains on the steps
Appearance: Brown, yellow, green or black spots on pool steps or corners.
Possible causes:
- Metallic deposits (copper, iron stains)
- Organic stains (leaves, decomposing plant debris)
- Presence of highly encrusting black algae
Solutions:
- Brush affected areas
- Identify type of stain (vitamin C test or direct chlorine)
- Apply a specific stain remover (organic or metallic)
- Adjust water balance to prevent recurrence
The essentials for correcting stains on the steps
Eau verdâtre
Greenish or yellowish water
Appearance: The water appears light greenish or yellowish, although it remains relatively clear.
Possible causes:
- Presence of oxidized metals (iron or copper)
- Reaction between chlorine and minerals
- Beginning of contamination by mustard algae
Solutions:
- Test water for metals
- Add a metal sequestering agent
- Adjust pH and apply a preventive treatment with a non-foaming algaecide
The essentials for correcting greenish or yellowish water
Green water
Green, black or brown water
Mustard algae, pink algae or black algae
Appearance: The water takes on a dark green, black or brownish hue, often accompanied by slipperiness on the walls.Green, black or brown water
Possible causes:
- Advanced algae blooms (green, black or mustard)
- Presence of metals in the water (iron, copper, manganese)
- Ineffective disinfection or filtration stopped
Solutions:
- Apply a shock treatment based on chlorine or peroxide
- Add an algaecide adapted to the type of algae
- Test for the presence of metals and add a sequestering agent if necessary
- Brush affected surfaces vigorously
Mustard algae
Pink algae
Black algae
The essentials for correcting green, black or brown water
Take your knowledge one step further with our tips and tricks
Are you in doubt?
Visual problems can quickly escalate if left untreated at source. A water test in-store or using a reliable kit will help you make the right diagnosis.
Consult our maintenance guide or come and meet one of our in-store experts to regain clear, healthy, sparkling water.
In store maintenance courses
Learn how to maintain your pool from our in-store experts.
Ready for more tips?
Consult our maintenance guide to learn how to extend the life of your pool and maintain its quality all season long.