HTH™ Pool Care pH Down

Pool pH Decreaser for High pH

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HTH™ Pool Care pH Down

Pool pH Decreaser for High pH

HTH™ pH Down is a sodium bisulfate pool pH decreaser that lowers high pH back into the safe 7.2-7.6 range.

  • Prevents cloudy water, scaling, and eye irritation
  • Target range: 7.2-7.6
  • Broadcast over deep end with pump running. Never pre-dissolve
  • Wait 4-6 hours after shocking before adding
  • Safe for vinyl-lined, fiberglass, concrete, and saltwater pools

Product Benefits

Fixes High pH Fast

High pH (above 7.8) reduces chlorine effectiveness dramatically, causes cloudy water, creates scale buildup on surfaces and equipment, and irritates swimmers' eyes. Bringing pH down to 7.2-7.6 lets sanitizer work properly and keeps water comfortable.

Addresses Stubborn High pH

If pH won't come down even after dosing, high total alkalinity is usually the cause. It will keep pushing pH back up. Since this sodium bisulfate formula also lowers alkalinity, you can often address both at once. If alkalinity is already in range, use smaller doses and retest frequently to avoid dropping alkalinity below 80 ppm.

Prevents Scale and Equipment Damage

High pH causes calcium scaling on pool walls, filter media, heater elements, and pump components. Scale buildup reduces heater efficiency, clogs filters, and creates rough, unsightly deposits on tile and plaster. Maintaining proper pH stops scale before it forms.

Safety and Application Notes

With the pump running, broadcast the dose evenly over the deepest part of the pool. Never pre-dissolve pH Down in a plastic bucket. Wait at least 48 hours before retesting. Wait 4-6 hours after a shock treatment before adding to avoid off-gassing. Safe for vinyl-lined, fiberglass, concrete, and saltwater pools when used as directed.

How to Use

How to Use

Why You Should Use This Product: This product lowers pH and total alkalinity in swimming pool water. Maintaining proper pH allows chlorine to work more effectively, helps reduce equipment corrosion, minimizes eye and skin irritation, and improves overall water clarity.

Before Use: Adjust total alkalinity first to help prevent pH drift. Measure pool water pH using an HTH test kit or test strips.

How to Add This Product to Your Pool

  1. Turn on the circulation pump.
  2. Broadcast this product evenly over the deepest part of the pool.
  3. Keep the circulation pump running.
  4. Wait at least 48 hours before retesting.

The pH should be measured each time a sanitizer is added. Use the dosage table below to determine the correct amount of product.

Dosage of pH Down

Pool Volume (Gallons) pH 8.0–8.4 pH >8.4
1,000 1.6 oz 2.4 oz
2,500 4 oz 6 oz
5,000 8 oz 12 oz
10,000 16 oz 24 oz
15,000 24 oz 36 oz
20,000 32 oz 48 oz

Ingredients

Ingredients

Active Ingredient:

Sodium Bisulfate: 92%

Constituents Ineffective as Adjuvants: 8%

Total: 100%

Safety, Storage, and Disposal

Safety

Warning: Causes skin and eye irritation. May cause respiratory irritation.

Avoid contact with eyes, skin, and clothing. Avoid breathing dust.

Wear goggles and rubber gloves when handling. Wash hands thoroughly after handling.

Remove contaminated clothing and wash before reuse.

Do not mix this product with any other chemicals.

First Aid

If in Eyes: Hold eye open and rinse slowly and gently with water for 15–20 minutes. Call a poison control center or doctor for treatment advice.

If on Skin or Clothing: Take off contaminated clothing. Rinse skin immediately with plenty of water for 15–20 minutes. Call a poison control center or doctor for treatment advice.

If Swallowed: Call a poison control center or doctor immediately. Have person sip a glass of water if able to swallow. Do not induce vomiting unless instructed. Do not give anything by mouth to an unconscious person.

If Inhaled: Move person to fresh air. If person is not breathing, call 911 or an ambulance, then give artificial respiration if possible. Call a poison control center or doctor for further treatment advice.

Storage and Disposal

Keep product dry in its original, tightly closed container. Store in a cool, dry, well‑ventilated area away from heat or open flame.

Use entire contents, then triple rinse and offer for recycling, or dispose in accordance with state and local regulations.

Do not reuse empty container.

Emergency Handling

If product becomes contaminated or decomposes, do not reseal container. Isolate container if possible. Flood decomposing product with large amounts of water to dissolve. Dispose of container and any remaining material according to local regulations.

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Quick Pool Tips

  • Always read product label directions prior to using and use only as directed

  • Always add chemicals to pool water, never the other way around

  • Never add chemicals to pool water when people are in the pool

  • Warning symbol with a triangle and exclamation mark on a blue background

    Never mix products together

  • Always store pool products in a cool, dry location and out of direct sunlight