Algae is a common problem in swimming pools.  What is it & how is it successfully prevented and treated. First of all, algae is a single-celled plant form. Some are aquatic (live in water), some are not.  Algae utilizes the process of photosynthesis to manufacture its own food. Algae comes in very wide variety of colors and forms making it adaptable to almost any condition.  Although some forms are virulent, most are harmless and pose no more than a nuisance to most pool owners.

Due to algae's microscopic size, it takes literally millions of these plants to accumulate to be noticed by the naked eye!  By that time it may be too late and very costly to correct.  Prevention of algae blooms is the best solution.  Click here for all of our Algae treating products.

The most common form of algae that we deal with in swimming pools is "green" algae.  Green algae (varies in color from blue-green to yellow-green to dark-green) can be free floating in the water (turning the water a hazy-green) or can be wall-clinging (patches of green). Wall-clinging varieties range in severity from small patches on pool walls and bottoms to virtually covering the entire pool surface. Green algae has the ability to clog filters and may even cause surface damage if left untreated.  Green algae can be treated fairly simply and quickly with a proper, aggressive shocking & algicide.

A relative of regular green algae is "small-celled green algae" (SCGA). The difference is seen in these areas:
1. The water remains relatively clear.  Many people treat the problem (without proper analysis) as a copper or mineral problem, however the metal chelants will show no effect. 
2. When treating with chlorine, chlorine seems to "disappear".  SCGA is very resistant to even high levels of chlorine.

Other mid-summer types of green algae noticed is "green spots" all around the pool, especially in shady areas. The water is almost always "very clear".  The water can have a "stinging" sensation. This is normal green algae, typically brought about by lack of homeowner care; i.e. not following a weekly maintenance routine such as the Once-a-Week 3 Step program combined with very low pH and very low Total Alkalinity.

Causes: typically poor routine maintenance. Lack of a regular sanitizing and / or algae prevention program (shock the pool & add algicide weekly for example).  Heavy bather loads combined with poor maintenance.  Excess trees & vegetation around the pool area.  Lack of direct sunlight on the pool. Source water contamination.  "Over-load" of nitrates or phosphates brought in through lawn or yard care treatments (not a true cause but more of an exacerbation of the problem).  Heavy rain (changes the water chemistry & causes a chlorine or other sanitizer demand).

Treatment:

1. Have water properly analyzed. BALANCE THE POOL WATER.  Proper pH, total alkalinity & calcium hardness are essential for the treatment to work.
    
2. Aggressively brush all areas that have visible algae in order to remove or loosen it from those surfaces.  Excessive algae should be vacuumed out of the pool on Direct Waste (if your filter is able).
    
3. Pools treated with chlorine or bromine should aggressively shock with chlorine (Burn Out or Smart Shock) and use a good quality algicide such as Spot Kill, Back Up, Algae All 60 or Banish in extreme cases.  Maintain a chlorine level of 3.0 ppm for several days.
    
4. Pools treated with SoftSwim or other Biguanides should top up their Bactericide level "B", add a double dose of algicide "A", and add a double dosage of shock or "C".
    
5. Follow up either method with Optimizer Plus. 

Prevention:

1. Maintain good, solid sanitizer levels all of the time.
2. Run the filter a minimum of 10 hours per day, everyday from opening to closing.
3. Vacuum the pool weekly.
4. Brush the pool walls & surfaces weekly (vacuuming doesn't count).
5. Shock the pool weekly.
6. Add algicide weekly.
7. Regularly clean solar blankets, ladders, pool toys, etc.
8. Use the pool.

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Treating algae with Sodium Bromide.  Click here for all of our Algae treating products.

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