hth® dual action start up, 1 kg

  • Soluble Granules
  • Shock treats & controls all algae, including black, green & yellow

Application instructions:

Use only a clean, dry scoop to measure this product. Do not use the scoop for any other purpose. DO NOT add this product to a floater, feeder or skimmer.

Opening your pool: This product is ideal for opening your pool or treating persistent algae. Distribute 180 grams of this product over the water's surface for each 10,000 L of pool water. This will raise the chlorine residual to 3.9 ppm, and provide 0.4 ppm of copper for algae control. If algae persist for more than one week, repeat dosage.

Routine Sanitization: For the remainder of the pool usage season, use hth® dual action 3” chlorinating pucks in accordance with label directions.

Shock treatment: This product should not be used as your regular weekly shock treatment. Shock treat weekly with an hth® shock product to kill bacteria, burn out organic contaminants, and keep water clear. Immediately after shock treatment, thoroughly clean pool surfaces by scrubbing and vacuuming through the filter. Do not enter the pool until the chlorine residual is 1-3 ppm as measured with hth® test strips.


Maintaining Proper Chlorine Levels

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Test Your Water

How often you should test and balance your pool water  can vary based on how often you use it and a number of other variables; but it’s important to remember that for chlorine and pH, you should usually test your pool two to three times a week. That may sound like a lot, but water balance is vital for your pool’s health and the health of the people who swim in it. When your pool water is out of balance, your sanitizers can be less effective, the water can cause irritation to the skin and eyes.  And if the water gets imbalanced enough, it can even damage the pool’s surfaces, structure, or equipment.

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Shock Weekly

In ideal circumstances, shocking your pool just once a week will keep it looking clean and clear, but any heavy rainfall, signs of algae, use by lots of swimmers, or periods of very sunny weather can deplete free chlorine levels, which means an extra dose of hth® Shock is needed. Sundown is optimum time to shock your pool because the chlorine can work without fighting the sun's ultraviolet rays and has more time to restore water clarity. 

HTH Pools - CL chlorine line graphic

Overstabilization: What is it?

While small levels of cyanuric acid (CYA) (20 – 40 ppm) do serve a purpose in protecting chlorine from sunlight degradation, too much can cause problems. Over-stabilization (> 90 ppm) is the buildup of cyanuric acid (CYA) in swimming pool water resulting from the use of stabilized sanitizers and stabilized shock products.  It significantly decreases the effectiveness of chlorine in killing germs, bacteria and algae.




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