Hot Tub Serum Turbo pH Down | Spa pH Decreaser

• 1 x Hot Tub Serum Turbo pH Down 1.5lbs resealable container, granular)

• Lowers high pH — brings alkaline water back into the safe 7.2–7.6 range
• Prevents scale and cloudy water — stops the buildup and haze that high pH causes
• Protects equipment — guards your heater, plumbing, and surfaces from scale and corrosion
• Boosts sanitizer efficiency — chlorine and bromine work far better at proper pH
• Also lowers total alkalinity — sodium bisulfate adjusts both, ideal when both run high
• Fast-acting granular — dissolves quickly and gets pH back in range

The active ingredient, sodium bisulfate, is a dry acid. When it dissolves it releases hydrogen ions that neutralize the excess alkalinity driving pH up — lowering both the pH and the total alkalinity of the water. Aim for a pH of 7.2–7.6, the range where water is clear, non-scaling, comfortable, and where your sanitizer performs at its best.

It's the mirror image of Turbo pH Up: where pH Up (soda ash) raises pH, Turbo pH Down (sodium bisulfate) lowers it. Because pH naturally creeps upward in a working spa, pH Down is the one you'll typically reach for more often.

Pro Tip: Broadcast it with the pump running and never add it to a spa with the circulation off. Sodium bisulfate is a concentrated dry acid, and a pile of it sitting on the acrylic shell can etch or bleach a spot. Spreading it across moving water lets it dissolve and disperse instantly, protecting the surface.

Never mix different products together in the same container. Add this product directly to the water with the circulation running. Test spa water frequently and adjust as needed, aiming for a pH of 7.2–7.6. Always follow the container label for exact dosing.

1. Test the water to confirm pH is above range.
2. Turn on the circulation system.
3. Broadcast the recommended amount of Turbo pH Down evenly over the surface of the water (see the label for the dose based on your spa's gallons and current pH).
4. Circulate 15–30 minutes and retest pH. If pH is still above 7.6, repeat until it sits between 7.2 and 7.6.

Pro Tip: Make pH adjustments before you shock, not after. Your sanitizer and shock work best in the 7.2–7.6 window, so getting pH right first means the chlorine or bromine you add next is far more effective — and you avoid wasting product fighting out-of-range water.

• Brand: Hot Tub Serum (Serum Watercare)
• Product Type: pH decreaser (balancer)
• Form: Granular
• Net Size: 1.5lbs
• Part Number: TU-014
• Active Ingredient: Sodium bisulfate
• Function: Lowers pH and total alkalinity
• Target Level: pH 7.2–7.6
• Dosage: Per container label, based on spa gallons and current pH
• Retest: Circulate 15–30 minutes, then retest and repeat if needed
• Compatible Sanitizers: Chlorine, bromine, salt, mineral, and ozone systems
• Application Note: Never mix with other products in the same container; broadcast over the water with the pump running
• Shipping: Standard ground; not classified as a hazardous material

Hot Tub Serum Turbo pH Down is compatible with all sanitizer systems — chlorine, bromine, salt, mineral, and ozone. As a balancer, it's part of the foundation you maintain alongside your sanitizer.

It's the counterpart to Turbo pH Up (which raises pH when it drops too low) and works alongside an alkalinity increaser and a reliable test kit or strips. Balance pH and total alkalinity before adding sanitizing and shock products. Never mix Turbo pH Down with other chemicals in the same container — always add it directly to the spa water.