SpaGuard pH Decreaser Tabs | Rapid-Dissolve Spa

• 1 x SpaGuard Rapid-Dissolve pH Decreaser Tabs — 1.25 lb (erosion-style tablets)

Note: These tabs lower pH (and total alkalinity). If you need to raise pH instead, that's a pH increaser. Apply tabs to the filter compartment, not the footwell, and don't leave undissolved material on spa surfaces. Keep the bottle tightly sealed and store in a cool, dry place away from other chemicals.

• Quickly lowers pH — brings high spa water pH back into the comfortable range.
• Precise 0.1–0.2 unit adjustment — one tab per 250 gallons for controlled, predictable dosing.
• Safer and easier than liquid acid — a clean dry tablet, no splashing or measuring corrosive liquids.
• Provides soaker comfort — balanced pH keeps water gentle on skin and eyes.
• Protects equipment and surfaces — prevents the scale and cloudiness that come with high pH.
• Convenient for frequent adjusters — easy to dose a tab at a time, as often as needed.

pH measures how acidic or basic your water is, with the spa target around 7.2–7.6. The pH of a spa naturally tends to drift upward over time, and when it rises too high the water becomes basic — minerals fall out of solution and form scale, the water clouds, and a growing share of your chlorine converts to a form that can't sanitize effectively. Lowering pH back into range corrects all of that.

These tabs are sodium bisulfate, a dry acid, compressed into an erosion-style tablet. Placed in the filter compartment with the jets running, each tab dissolves within a few minutes and releases acidity that neutralizes excess, lowering pH (and total alkalinity) by a controlled 0.1–0.2 units per tab per 250 gallons. Unlike some of SpaGuard's other rapid-dissolve tabs, these don't effervesce — they dissolve steadily by erosion — but they still disperse quickly. The controlled per-tab adjustment is what lets you reach your target precisely instead of overshooting into low, corrosive pH.

Pro Tip: Get total alkalinity in range first. Alkalinity buffers pH, so it should read at least around 125 ppm before you fine-tune pH — otherwise pH will keep drifting and you'll be dosing constantly. Balance alkalinity, then adjust pH a tab at a time.

1. Test the pH of your spa or swim-spa water. The target range is 7.2–7.6. Confirm total alkalinity is at least 125 ppm before adding this product.
2. Determine the number of tabs needed from the chart on the label, based on your current pH. As a guide, 1 tab per 250 gallons lowers pH about 0.1–0.2 units.
3. With gloves, apply the tab(s) directly to the filter compartment with the jet pump running, when the spa is not occupied. Do not apply to the footwell — it dissolves more slowly there and isn't recommended.
4. Retest pH after at least 15 minutes and adjust as necessary.
5. If applying directly to the water, brush away any undissolved material; never leave undissolved tabs on spa surfaces.

Pro Tip: Always follow the dosing chart and directions on your bottle's label, which take precedence over any general guidance. Apply to the filter compartment with jets running for the fastest, most even dissolution.

• Product: SpaGuard Rapid-Dissolve pH Decreaser Tabs — Spa Water Balancer
• Brand: SpaGuard (BioGuard family)
• SKU: 42662BIO
• Size: 1.25 lb
• Form: Compressed erosion-style tablets (dissolve in minutes; do not effervesce)
• Function: Lowers pH and total alkalinity
• Active Ingredient: Sodium Bisulfate 93.2%
• Adjustment: ~0.1–0.2 pH units per tab per 250 gallons
• Target pH: 7.2–7.6
• Alkalinity Before Use: At least 125 ppm
• Application: Filter compartment, jets running, spa unoccupied; not the footwell
• Retest: After at least 15 minutes
• Suitable For: Spas and swim spas
• Sanitizer Compatibility: Chlorine, bromine, ozone, and saltwater/mineral
• Surface Compatibility: Safe for all common spa surfaces (don't leave undissolved material on surfaces)
• Country of Origin: Made in USA
• Shipping: Ships UPS Ground only (confirm from backend)
• Hazmat Classification: Regulated acid (sodium bisulfate) — classified as a hazardous material; ships ground only

pH Decreaser Tabs are a water balancer that works with whatever sanitizing system you use:

• Chlorine spas — fully compatible.
• Bromine spas — fully compatible.
• Ozone systems — compatible as part of a balanced-water routine.
• Saltwater / mineral systems — compatible.
• Spas and swim spas — formulated for the smaller volumes and higher temperatures of spas.
• All spa surfaces — safe for use with all common spa surfaces (don't leave undissolved tabs resting on surfaces).

Important: pH Decreaser Tabs are a balancer, not a sanitizer. They correct water chemistry but don't sanitize — use alongside your regular sanitizer and shock.