Algae problems in pool water

Pool water problem - algae

Algae is the most common pool water problem only because it is the most visibly obvious one. Algae in itself is not dangerous - in fact it is the main ingredient in many health supplements and tablets. Algae brings danger in that it converts sunlight into food, releasing wastes that become the feeding grounds for unwanted and harmful bacteria and other micro-organisms.

There are well over 20,000 species of algae, only a few of which are encountered in swimming pool water. Algae is almost constantly entering the pool, and as soon as the sanitizer level drops too low, the algae begins to take hold and multiply. It takes as little as a few hours on a warm sunny day for your sparkling pool to develop an algae problem. The algae "spores" found in the air are from algae that has dried out (at a nearby stream, from a neighbor's pool . . .) and become airborne with the breeze.

Types of pool algae

Algae in swimming pools is often referred to by its color:

  • green algae - by far the most common and relatively easy to treat;
  • yellow/ mustard algae - troublesome to treat but also relatively susceptible to treatment;
  • black algae - can be very difficult to get rid of, especially in plastered pools;
  • pink algae - not an algae at all, but is a fungus called Paecilomyces lilacinus that causes slimy white, pink or grey colonies.

Preventing pool algae

Maintaining proper water balance and minimum sanitizer levels will ensure that any algae spores entering the pool water cannot take hold. Most pools use chlorine, which should be kept at a minimum level of 1.0ppm. Using the Pool Wizard or any similar mineral system may allow you to keep the free chlorine level at 0.5ppm or lower without the risk of developing an algae problem.

Destroying pool algae

Once algae has been allowed to bloom, it is quite tiresome to destroy. The common steps to get rid of an algae problem are:

  1. Shock treat the pool. If you are using chlorine, aim for at least 10ppm free chlorine (10 times the recommended minimum level).
  2. Circulate the water round the clock if possible.
  3. Brush the pool and vacuum.
  4. Add a commercial algaecide prepared for the algae you have (green, mustard or black) according to the instructions.
  5. Repeat brushing and vacuuming daily if possible. Add more chlorine if the level falls below 5ppm.
  6. Clean or backwash your filter regularly.

The Pool Wizard and pool algae problems

The Pool Wizard was developed to destroy algae and bacteria, and prevent their recurrence in swimming pool water. The 24/7 protection the minerals claim to provide may help prevent algae and bacteria from multiplying in pool water even when chlorine levels hit zero for a couple of days. With the Pool Wizard, algae may becomes something you find only in that health supplement you take every morning, and not something you see in your pristine blue pool.


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Pool Wizard solves pool algae problems in a flash