Swimming Pool Algaecides

Swimming Pool Algaecides

Swimming Pool Algaecides

Since the dawn of swimming pools, scientists and chemists have labored to produce effective solutions to algae problems. Tens of thousands of distinct algae species exist, but fortunately only a handful have both the opportunity and ability to grow in a swimming pool.

Pool algae is a harmless form of cyanobacteria, aquatic life that use photosynthesis to produce an energy and food source. Algae can be free floating, or it can grow in sheets on the walls and floors, and some types of pool algae can survive inside of pipes or filters.

Types of Pool Algae

Green algae or blue-green algae is the most common type; and like most plants, all it needs to survive is sunlight, water and warmth.

Yellow algae are another form of green algae, tinted with yellow carotenoids. It can become chlorine resistant, and can survive without sunlight.

Red algae belong to a different genus of bacteria, and in pool terminology, may also be called pink algae or pink slime. Also chlorine tolerant, and can live without sun.

Black algae are a strain of blue-green algae that prefers plaster pools, where it can put down roots. Thick multi-layered cap protects the organism from chlorine and most algaecides.

Types of Pool Algaecides

To prevent pool algae, algaecides play an important role. They can be used as an algae-cide to kill small, isolated blooms, but most perform best as an algae-stat, to control and prevent pool algae growth. Pool algaecides are formulated to kill all algae types, but some control certain strains of pool algae better than others, and different algaecides each have their own way of controlling algae.

Quat Pool Algaecides or Quaternary Ammonium compounds, are technically detergents which is why overuse can cause some foaming to the pool. Quats function as microbial disinfectants, by attaching themselves to negatively charged algae cells. Once attached, they dissolve the outer protective membranes, which allows your chlorine to penetrate the organism’s nucleus. Quats are the most economical pool algaecide to buy, and are typically sold in 10% and 50% concentrations or strengths.

Algaecide 10 - Algaecide 50

Polymer Pool Algaecides are technically Poly-Quat compounds with long carbon chains, with the advantage of being both non-foaming and non-staining. Polymers have a positive charge and once attached to the negatively charged algae, they quickly spread over the surfaces, smothering the cell. Poly-Quats are twice as effective and longer lasting than Quat algaecides, but also the most expensive. Polymer algaecides are a popular multi-season pool algaecide and is typically sold in 30% and 60% concentrations or strengths.

Algae-Clear - Algaecide 60 Plus

Metallic Pool Algaecides contain Copper ions, used for thousands of years in water treatment. The copper is chelated or bonded with amino acids to reduce possible staining from overuse, primarily a concern for plaster pools. Like other algaecides, metal ions are positively charged and attach themselves to algae, where they penetrate the outer cell walls, poisoning the enzymes within the algae nucleus. Works well on black algae, and effective for green algae blooms. Mid-range price copper algaecides are most often a 7% elemental copper concentration or strength.

Super Algaecide - Black Algaecide - Sea-Klear 90 day

Sodium Bromide is not technically an algaecide, but is used with granular chlorine (pool shock) as a catalyst to convert the bromides into the potent algae killer, hypobromous acid. Called a Chlorine Enhancer by some chemical manufacturers, sodium bromide creates a synergy of high chlorine and high bromine levels. Bromides are usually used not for algae control, but to kill pool algae in out-of-control cases. Works well with yellow algae, or green algae that is not responding to very high levels of chlorine alone.
Yellow-Out - Green to Clean - Swamp Treat - No Mor Problems

Tips on Using Pool Algaecides

  • Follow Label Instructions: Read the complete label for dosage instructions, and water balance recommendations before adding an algaecide to the pool.
  • Pool Shock Destroys Algaecide; Never add pool shock and algaecide at the same time. Wait until chlorine level drops below 5 ppm, before adding algaecide.
  • Balanced Pool Water; Avoid high pH, Alkalinity or Calcium Hardness levels, and have a 2-3 ppm chlorine reading on your test kit.
  • Don’t Overdose with Algaecide; Read and follow label instructions for correct dosage to match your pool size in gallons.
  • Clean the Pool; Heavy organic material in the pool (leaves and lawn debris) consumes algaecide and makes it less effective.
  • Circulation and Filtration; Helps to distribute the algaecide and remove suspended matter. Algaecides have little effect on stagnant water.

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