About Slightly Acidic Electrolyzed Water


Generated by electrolysis using only dilute hydrochloric acid with a concentration of 3~6% as raw material. Based on the method of producing "slightly acidic hypochlorous acid water" as stipulated in the Food Sanitation Act No. 125.
Sodium chloride (NaCl) is not used, so there is neither salt precipitation nor the generation of bromic acid, as it is as safe as tap water.
The pH of the human skin ranges from 4.5 to 6.0, and the pH of AQUAHEART is 5.0 to 6.5, which is approximately the same range, making it very gentle to people and the environment.

Hypochlorous acid (HOCI) is a completely different compound than sodium hypochlorite (NaCIO).

Differences between Sodium Hypochlorite


Since the pH of the slightly acidic solution is the same range as that of human skin, it does not cause skin irritation.

The three classifications of acidic electrolyzed water are Strongly Acidic Electrolyzed Water (pH 2.7 or lower), Weakly Acidic Electrolyzed Water (pH 2.7~5.0), and Slightly Acidic Electrolyzed Water (pH 5.0~6.5), depending on acidity. Of these, AQUAHEART, slightly acidic electrolyzed water, is characterized by its high sterilizing effect, almost odorlessness, and gentleness to the skin.


※Slightly Acidic Electrolyzed Water with pH 5~6.5 can be used without worrying about the generation of chlorine gas. It is mostly comprised of hypochlorous acid, which is the basis of the sterilizing effect, so it can be used safely and efficiently for sterilization.

※Since the hypochlorous acid ratio is about 5%, higher concentrations, about 200 ppm, is required to increase the sterilizing effect, resulting in chlorine odor and other problems.

Minimal residue and no environmental impact even when used in large quantities (even in wastewater).

Comparison of natural evaporation of residue on a petri dish

AQUAHEART (Slightly Acidic Electrolyzed Water) is made from purely light hydrochloric acid (3-6% concentration) and contains no Na (sodium), so it produces almost no residue (salt) and is safe, with no effects on metals (salt corrosion, etc.) or the environment as it is essentially equivalent to tap water.

Achieved more than 99.9% neutralization of space-filled bacteriophage MS2 (non-envelope virus)

In accordance with ASTM (global standard), it was found that more than 99.9% of viruses were neutralized after 60 minutes by diffusion of Slightly Acidic Electrolyzed Water atomized by an ultrasonic humidifier, when continuously supplied to a space of approximately 29㎡.

How to Store

Hypochlorous acid (HOCI) gradually decreases in effectiveness over time, so spray products should be used up as soon as possible after opening (May vary depending on the date of manufacturing), and should be stored in a refrigerated area in hot and humid environments such as summer.

Ingredients and Manufacturing Process

Hypochlorous acid (HOCI) is also produced within the human body (white blood cells) and plays an active role in the fight against bacteria and viruses that have invaded the body.


Food Sanitation Act No. 125 "(Slightly acidic) Hypochlorous acid water".

”Slightly Acidic Electrolyzed Water" was the common term since it was officially announced in the Official Gazette No. 3378 on June 10, 2002 (approved and designated as a food additive sterilization agent).

Effective Chloride Concentration

When it was first approved on June 10, 2002, the lower limit was set at 10 mg/kg, a concentration that would allow sterilization without damaging the taste or aroma of food, and the upper limit was set at 30 mg/kg, as higher concentrations could not be expected to improve sterilizing effectiveness. Subsequently, Slightly Acidic Electrolyzed Water made by adding salt water to hydrochloric acid was also approved under the Food Sanitation Law, and the current effective chlorine concentration ranges from 10 to 80 mg/kg (pH remains the same).

Manufacturing Processes


Electrolysis of hydrochloric acid (designated source agent) in a non-diaphragm electrolysis tank


Qualitative Analysis of Effective Chlorine Concentration and pH


Completion of Slightly Acidic Electrolyzed Water (AQUAHEART)

Chemical Formula
2Cl → Cl2+2e Cl2+H2O → HOCl+HCl

Hydrochloric acid with 3~6% concentration is supplied to the non-diaphragm electrolyzer via a pump, where it is electrolyzed, diluted and mixed with tap water in the main piping to produce Slightly Acidic Electrolyzed Water (effective chlorine concentration: 10~40mg/kg, pH: 5.0~6.5)

Results of Various Testing

Test results for "water for food products (water suitable for drinking)" based on the Food Sanitation Act.

Results of a safety trial of AQUAHEART's 100% pure Slightly Acidic Electrolyzed Water

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