Hanna Instruments Alkalinity Chemical Test Kit (0–100 / 0–300 mg/L, 110 Tests) (HI3811)

Hanna Instruments Alkalinity Chemical Test Kit (0–100 / 0–300 mg/L, 110 Tests)

The HI3811 is a titration-based chemical test kit designed to measure both Phenolphthalein Alkalinity and Total Alkalinity in water samples. It covers two ranges — 0 to 100 mg/L and 0 to 300 mg/L as CaCO3 — making it suitable for pool water, drinking water, wastewater, and a wide range of environmental and industrial applications. Each kit contains enough reagents to perform approximately 110 tests.

How it works

The HI3811 uses an acid titration method with two colour indicators: phenolphthalein and bromophenol blue. Phenolphthalein Alkalinity is determined by neutralising the sample to pH 8.3, capturing hydroxide and carbonate contributions. Total Alkalinity continues the titration to pH 4.5 to quantify all carbonate and bicarbonate ions. The volume of titrant consumed — dispensed accurately via the included calibrated syringe — directly indicates the alkalinity concentration at either 1 mg/L or 3 mg/L resolution depending on the selected range.

What’s included

The kit ships complete and ready to use: 10 mL phenolphthalein indicator, 10 mL bromophenol blue indicator, 120 mL alkalinity titrant, a 10 mL calibrated vessel, a 50 mL calibrated vessel, and a calibrated syringe with tip. All reagents are pre-made and labelled with expiration date and lot number for full traceability. When reagents run out, a replacement reagent set can be ordered separately — no need to purchase a new kit.

Why monitoring alkalinity matters

Alkalinity is a key indicator of water’s buffering capacity and its resistance to pH swings. In pool water, low or unbalanced alkalinity can cause corrosive conditions that damage surfaces, equipment, and piping. Regular testing with the HI3811 helps pool owners and water treatment professionals maintain stable water chemistry, protect infrastructure, and ensure water safety across pools, potable water systems, and beyond.