The pH of the water is an important factor since at lower pH levels the corrosion rate increases. If the alkalinity values are sufficiently high, it will not be difficult to control the pH. Most pool managers prefer to keep the pH between 7.2 and 7.4 to best maintain low corrosion rates and a sufficient activity of chlorine.
Chlorine is a strong oxidising agent that destroys organic pollutants and bacteria. Chlorine combines with compounds containing nitrogen to form chloramines, during which only part of the chlorine will be used while the rest remains active, continuing it’s disinfecting action.
Combined chlorine is the quantity of chlorine that has already combined with nitrogen containing compounds. It is much less effective as a disinfectant than free chlorine. The addition of combined chlorine and free chlorine gives total chlorine. A pool manager needs to aim for the perfect balance where free and total chlorine are proportionally equal, and thus to keep the combined chlorine levels near zero. The presence of chloramines is undesirable because of the distinctive ‘swimming pool smell’ as well as irritation to the eyes and mucous membranes caused by combining chlorines like dichloramines.
Commercial chlorine for disinfection may be available as a gas (Cl ), a liquid like sodium hypochlorite or bleach (NaOCl) or in a solid state like calcium hypochlorite, chlorohydantoins or chlorocyanuric acid compounds. These compounds, once dissolved in water, establish equilibrium between the hypochlorous acid (HOCl) and the hypochlorite ions (OCl¯). Although both forms are considered free chlorine, it is the hypochlorous acid that provides the strongest disinfecting and oxidising characteristics of chlorine solutions. The amount of hypochlorous acid in chlorinated water depends upon the pH value of the solution. Changes in pH value will affect the HOCl equilibrium in relation to the hydrogen and hypochlorite ions.
Microorganisms grow more rapidly at higher temperatures, so the required sanitisation level in a swimming pool or spa is highly dependent on the water temperature; this is especially concerning for heated pools and spas. A general rule of thumb is that for every 5.5°C increase in water temperature over 27°C, the concentration of required sanitizer is doubled.
Turbidity is a measurement of the cloudiness or haze of the water. Swimming pool, hot tub, and spa water can have varying degrees of cloudiness from the indiscernible to very noticeable when the bottom of a pool cannot be seen. The cloudiness or haze can be a symptom of a variety of problems from biological forms, including algae and bacteria to precipitate such as calcium carbonate that will appear at elevated pH levels. Back flushing, filter cartridge replacement, adding flocculants, or a simple pH adjustment can sometimes resolve the increase in water turbidity. The remedy is determined by the cause of the increase in turbidity. The turbidity of a swimming pool, hot tub, or spa should be kept low at a value of 0.5 FNU/NTU or less.
Once you have established the sanitation options, all you have to do is test your water regularly so that it remains clean and bather-friendly.
Depending on the sanitation option you have chosen (automatic or manual) for disinfection there are several options to test the water with practical handheld devices.
HI971044 Pool Line Portable Photometer
Photometer is designed to measure pH, Alkalinity, Free & Total Chlorine, and Cyanuric Acid in swimming pools, hot tubs, and spas. This photometer combines accuracy and ease of use in a simple, portable design. The advanced optical system provides lab-quality accuracy while its user-friendly design is easy for any user, making it the perfect photometer for your water quality testing needs.
- No warm up time before taking a measurement
- Tutorial mode for step-by-step instructions
- CAL Check to verify meter performance
HI981954 Pool Line Multiparameter Waterproof Portable pH/ORP/EC/Temperature meter
is made for measuring key water quality parameters in swimming pool, hot tub, or spa water. This is an advanced meter uses a single weighted probe with multiple sensors to measure multiple parameters simultaneously and display results as pH, pH in mV, ORP, conductivity (EC), total dissolved solids (TDS), salinity, and temperature.
The meter has a built-in pressure transducer for barometric pressure readings.
- One probe with field replaceable pH/ORP, EC and temperature sensors
- Auto-ranging for EC and TDS readings
- Display up to 11 measurements simultaneously
HI981914 Pool Line Professional Waterproof Portable pH/ORP meter
is made for measuring pH and ORP of a swimming pool, hot tub, or spa water. This is an advanced meter with many features including Hanna’s exclusive CAL Check pH electrode diagnostics that is used to identify potential problems, including when to clean the electrode, check a buffer for contamination and the overall health of a pH electrode. This function can be used to identify issues with process probes that have a BNC connector.
- Laboratory grade measurements in a portable
- CAL Check advanced probe diagnostics
- Troubleshooting tool for the maintenance of process probes
ORP/Temperature Pool Line Tester – HI981204
HI981204 Pool Line ORP and temperature meter is made for measuring the oxidation (chlorine) level of swimming pool, hot tub, or spa water. This lightweight, waterproof tester offers high accuracy ORP, and temperature measurements in a single handheld unit.
- Replaceable ORP electrode
- Simultaneous display of ORP & temperature
pH/ORP/Temperature Pool Line Combo Tester – HI981214
pH/ORP meter is made for measuring pH and ORP of a swimming pool, hot tub, or spa water. This lightweight, waterproof tester offers high accuracy pH, ORP, and temperature measurements in a single handheld unit. No more switching between meters for your routine measurements.
- Replaceable pH electrode
- Automatic calibration
HI981274 pH and Temperature Tester
Tester with 0.1 pH resolution
This meter also features the HI73127 replaceable electrode with a stainless steel round connector. This cartridge design has no pins which could bend or break.
HI981074 Pool Line pH and temperature meter is made for measuring the pH of swimming pool, hot tub, or spa water. This modern looking meter is only 0.7″ thick and extremely ergonomic, fitting comfortably in your hand. This tester keeps things simple with a two-button operation; one for ON/OFF, the other for Calibration.
Waterproof Pocket pH Tester with 0.1 Resolution
HI985394 Pool Line Digital Thermometer
uses a weighted, stainless steel probe with a 3 m (9.9’) flexible, silicone cable.
The probe incorporates an NTC thermistor sensor, providing an extremely accurate temperature measurement at a variety of depths in swimming pools and hot tubs.
- CAL Check™ to verify internal electronics of the meter
- Selectable °C/°F readout
- Weighted AISI 316 Stainless Steel Probe
HI7014 The Hanna Free Chlorine Checker® Handheld Colorimeter (HC)
bridges the gap between simple chemical test kits and professional instrumentation. Chemical test kits have limited accuracy and resolution since they rely upon the human eye to discern differences in color.
Professional instrumentation incorporates a light source at a specific wavelength and a light-sensing detector to precisely determine absorbance and ion concentration. The Pool Line Free Chlorine Checker® HC uses a fixed wavelength LED and silicon photo detector to provide the accuracy of professional instrumentation at the affordable price of a chemical test kit.
- Precise measurements with no guessing of color
- Laboratory measurements at a fraction of the cost
- Simple, intuitive operation
HI987134 Pool Line ISO Portable Turbidity Meter
The HI987134 is a high accuracy portable turbidity meter. The meter is supplied complete with AMCO-AEPA-1 primary turbidity standards used for calibration and performance verification. The HI987134 meets and exceeds the requirements of the ISO 7027 Method for turbidimetric measurements.
- Fast Tracker™ – Tag Identification System (T.I.S)
- USB for data transfer
- Up to four-point calibration
HI95654 Thermo-hygrometer with Dew Point and Calibration Data-Logging Probe
is a portable thermo-hygrometer designed to measure temperature and Relative Humidity (RH). HI95654 can also calculate the dew point from the temperature and RH.
To ensure maximum protection against the effects of humidity and condensation, the instruments are housed in a rugged, water-resistant casing.
The temperature and RH probe is a “smart probe” which consists of a factory calibrated electronic sensor which requires no user calibration.
Our “smart probes” will work with any of our meters without the need to recalibrate the electronic sensor tracks the performance and stores the calibration history directly onto the probe.
• Simultaneous RH and temperature measurements on a large, dual-line LCD display
• Waterproof casing IP67
• MIN, MAX value and HOLD indicator
HI968014 Digital Refractometer
for Liquid Chlorine
- Ideal for the analysis of:
- The dual-level LCD displays measurement and temperature readings simultaneously
- ATC – Automatic Temperature Compensation
- Easy measurement:
Place a few drops of the sample in the well and press the READ key
As additional to our family of test kits, we have several NEW!
Pool Line Hydrogen Peroxide Test Kit – HI38444
HI38444 Pool Line Hydrogen Peroxide Test Kit is used for the measurement of hydrogen peroxide levels in swimming pools and spas.
- Supplied complete with enough reagents to perform up to 100 tests (average)
- Has both low range (0.00 to 2.00 ppm H2O2) and high range (0 to 10 ppm H2O2)
- Uses a drop-count iodometric titration method
HI38904 – Pool Line Quick Total Hardness Chemical Test Kit
HI38904 Pool Line Quick Total Hardness (TH) Chemical Test Kit is a basic test for the measurement of total hardness, as CaCO3, in swimming pools, hot tubs, and spas.
- Pre-made reagents for ease of use
- All reagents marked with expiration date and lot number for traceability
- Manual titration performed with color indicator with a range to 800 ppm
HI38434 – Pool Line Bleach Test Kit
HI38434 Pool Line Bleach Test Kit is used to determine the concentration of sodium hypochlorite (bleach) that is added to swimming pools, hot tubs and spas. This test kit can measure from 50 g/L (5%) to 150 g/L (15%).
- Supplied with enough reagents to measure up to 100 tests on average
- Wide range up to 150 g/L (15%) Chlorine (Cl2)
- Iodometric drop type titration method
IN-LINE CHLORINE SANITATION
Pools with in-line chlorine sanitizing systems, dispense chlorine and important minerals into the water automatically. This maintains a constant residual amount of chlorine, which prevents bacterial growth and eliminates contaminants. The minerals inhibit bacteria growth and soften the feel of the water.
These systems remove the need to continually test and adjust multiple chemical levels of the water on a daily and weekly basis.
pH/ORP Controllers – BL122 • BL123
Designed to maintain constant pH and disinfectant levels in swimming pools, hot tubs, and spas, the BL122, and BL123 pH and ORP controller offers the added benefit of allowing remote connection and access to devices via the Hanna Cloud web app.
- Keep track from anywhere with Hanna Cloud connectivity.
- Inline or panel mounted models.
- Built-in datalogger for compliance monitoring
BL122 and BL123 are designed to maintain constant pH and disinfectant levels in swimming pools, hot tubs, and spas and offer the added benefit of allowing remote connection and access to devices via the Hanna Cloud web app. These controllers are available in two configurations. The basic version is the inline model which allows for direct installation of probe and chemical injection fittings into existing piping. A panel mounted version with a bypass flow cell is also available. The bypass flow cell allows for calibration and maintenance of the probe without having to shut down the recirculation pump.
Let your dream take you beyond Clouds!
Hanna Cloud is a web-based application that connects you to measurement devices such as the BL122 and BL123. Measurements and data storage are accessible from your PC, tablet or phone. Measurements, trends, history, device settings, alarms, and messages are transmitted to your “Dashboard” as your instrument measures and controls your process.
pH/ORP Controllers – BL120 and BL121
The BL120 Swimming Pool Controller is a complete system designed for maintaining swimming pool, hot tub, and spa disinfection water quality. The BL120 is available in two configurations. The basic version is the in-line model which allows for direct installation of probe and chemical injection fittings into existing piping. The other version is a panel mounted version with a bypass flow cell. The bypass flow cell allows for calibration and maintenance of the probe without having to shut down the recirculation pump. Additional features of the BL120 include LED indicators for dosing, meter status and service, real-time graph display, programmable alarms, and password protection.
with Built-In Chemical Feed Pumps
These Swimming Pool Controllers are a complete system designed for maintaining a swimming pool, hot tub, and spa disinfection water quality. These controllers are available in two configurations. The basic version is the in-line model which allows for direct installation of probe and chemical injection fittings into existing piping. A panel mounted version with a bypass flow cell is also available. The bypass flow cell allows for calibration and maintenance of the probe without having to shut down the recirculation pump.
Pool Line ORP Controller and Dosing Pump – BL101
Engineered to be an inexpensive solution for homeowner and maintenance companies to maintain the ideal ORP at all times of a swimming pool or hot tub. The BL101 Pool Line ORP Controller and Dosing Pump are a complete solution with both a process controller and a chemical dosing pump. Simply insert the probe and injection valve in-line with the re-circulation pump and supply the oxidizer (i.e. chlorine) to be dosed.
- All in one solution for maintaining the proper ORP value
- Industrial process probe with 1/2″ NPT threads for insertion into re-circulation line
- Input for level controller or flow switch
BL100 pH Controller and Dosing Pump
is a system engineered for maintaining the pH of swimming pools, hot tubs, and spas. Typically chlorine, whether liquid or solid, is alkaline and will raise the pH of the water that it is added to. As the pH increases above pH 7.4, a form of chlorine known as hypochlorite ion (OCl-) increases. This form of chlorine is 100 times less effective at killing bacteria as compared to the other form of chlorine known as hypochlorous acid (HOCl). For this reason it is important to maintain the correct pH level in order to ensure that the more powerful hypochlorous acid form is available for disinfection. The BL100 was developed to be an inexpensive solution for the consumer to maintain the ideal pH at all times. Simply insert the probe and injection valve in-line with the recirculation pump and provide the chemical to be dosed.
- All in one solution for maintaining the proper pH
- Industrial process probe with 1/2″ NPT threads for insertion into re-circulation line
- Input for level controller or flow switch
Pool Line pH and mV Precision Simulator – HI9310014
HI9310014 is a portable pH/mV simulator designed specifically for testing pH and mV (ORP) meters. It’s a great diagnostic tool for testing pH/mV meters including process controllers.
- Simulate pH from 0 to 14 and mV from -1000 to 1000 mV
- Works with all meters with a BNC connector
- Invaluable diagnostic tool for Service and Maintenance Personnel
With 60 offices in 47 countries, Hanna strives to be a worldwide leader in service and selection.
Offering research grade quality at competitive prices, every Hanna office strives to work with each customer to develop a solution tailored to their needs, on their budget.