Precision aquarium EC/TDS testing meter at an economical price
Measures Electrical Conductivity (EC) in µS or mS and Total Dissolved Solids (TDS) in ppt or ppm
Water-resistant electronic handheld meter boasts simple push button digital calibration
Economical, handheld meter puts fast and accurate EC/TDS measurement in the palm of your hand. The HM Digital EC/TDS HydroTester COM-80 is a great choice for hobbyists looking for a sensibly priced electronic tester that measures EC (Electrical Conductivity), TDS (Total Dissolved Solids) and temperature. Water-resistant combination meter measures parameters in four different scales allowing for a variety of uses and greater versatility and accuracy. Handheld EC/TDS meter is the budget-friendly choice to ensure your reverse osmosis unit is producing the purest, highest quality water for aquarium use.
Precision device boasts advanced microprocessor technology to ensure exceptional reliability. User-friendly features including multiple parameter measurement, easy-to-read LCD screen, auto-off function, automatic temperature compensation, factory calibration and more keeps high-tech water testing simple! EC measurement range of 0-9990 µS; 0-9.9 mS. TDS measurement range of 0-5000 ppm (mg/L); 0-5.0 ppt. EC and TDS resolution of 1 µS/ppm. Temperature measurement range of 33-176°F with a resolution of 0.1°F. All measurements are accurate within +/-2%. Includes a protective cap and batteries.
What are EC and TDS?
As a general definition, EC (Electrical Conductivity) is a substance's ability to conduct electricity, whereas TDS (Total Dissolved Solids) is the combined total of any minerals, salts, or metals dissolved in water or other liquids. Both can be used as measurements either to determine water purity or to determine the quantity of nutrients in a solution and other applications. The CON-80 feature two scales for EC and two scales for TDS. For both EC and TDS, the lower the number, the purer the water, with zero being the closest to pure H2O.
Measures electrical conductivity (EC), total dissolved solids (TDS). Excellent for nutrient testing
The COM-80 is ready for immediate use, but please familiarize yourself with the modes and parameters. This will help you get the most out of this instrument.
Scales/Units of Measurement for EC (Electrical Conductivity)
µS = micro-Siemens
mS = milli-Siemens (1 mS = 1,000 µS)
Scale/Unit of measurement for TDS (Total Dissolved Solids)
Ppm = part per million
Ppt = parts per thousand (1 ppt = 1,000 ppm)
Taking EC or TDS Measurements
Remove the cap (do not use the cap for testing).
Click the POWER button. The reading will always be zero in the air.
Dip the meter's sensor into the water, liquid or solution to be tested.
Lightly swirl the meter to ensure the removal of air bubbles or electrical charges.
The meter will display a reading instantly. Keep the meter in the water until the reading stabilizes (up to five seconds, depending on the situation).
To view the reading out of the liquid, click the HOLD button. This will freeze the reading on the screen. Clicking HOLD again will release it.
Click the POWER button to turn the meter off.
Shake any excess water off the meter and rinse with low TDS water (such as distilled, RO, or DI) or use compressed air to clean it,. Put the cap back on.
With the meter on, press and hold the MODE button.
The scales will cycle through on the display screen in this order:
mS > µS > ppt > ppm > mS
Release the MODE button when the desired scale is shown.
Temperature and Switching Temperature Modes
The temperature reading is always displayed on the LCD panel (except in calibration mode) and is shown simultaneously with EC/TDS readings.
The default mode for temperature is Celsius. To change the temperature mode, quickly click the TEMP/CAL button to switch from Celsius to Fahrenheit or vice-versa.
Care and Maintenance
If using the COM-80 for nutrients or high TDS solutions, ALWAYS rinse the sensor after each use. Rinse in distilled or RO water but tap water can also be used. Improper care will negatively affect readings and void warranty.
Your meter has been factory calibrated, which is sufficient for most applications. The COM-80 will retain its calibrations for a long period of time but recalibration may be necessary based on frequency of use, care and application of use.
Ideally, store the sensor dry (it should never be stored in water or a solution).
Calibrating a scientific instrument is similar to tuning a musical instrument. Your COM-80 has been factory calibrated to 1413 µS (700 ppm), which is suitable for most applications and is ready for immediate use. The meter will retain it calibration for many years, depending on care, frequency of use and application of use. If you need to recalibrate:
Obtain a certified EC/TDS calibration solution. Always calibrate close to the level you will be testing (or in the middle of the range).
Turn the meter on and insert into the solution (make sure the meter's mode matches the composition of the solution). If your meter shows the correct reading, stop here. If not, press and hold CAL button for five seconds. The display will flash and the temperature reading will change to a flashing 'CAL' image.
Adjust the reading to match the solution value with the UP or DOWN buttons (indicated by the arrows). When the number matches the solution, click ENTER.
'CAL' will flash briefly, indicating progress. Allow a few seconds, do not press any buttons, and if possible do not move the meter.
When the meter is calibrated, 'End' will flash and the measurement will reappear.
If you need to calibrate the COM-80's thermometer, only calibrate it in the air to a different, correct thermometer.
With the meter OFF and in the air, press and hold the POWER and TEMP buttons at the same time for 2 seconds.
'CAL' and the temperature will flash on the screen.
Using the UP or DOWN buttons (arrows), adjust to the correct temperature.
Once you have corrected the temperature, click ENTER. 'C - CA - CAL' will flash on the screen and then 'END' will briefly appear. The thermometer is now calibrated.
Changing the Batteries
When the meter displays a flashing battery symbol, your batteries are getting weak and should be replaced soon. To change the batteries:
Pull out the orange battery compartment using your thumbnail.
Remove the three batteries.
Insert new batteries in the directions as depicted inside the compartment. The flat side of the battery is the positive (+) side. The meter uses LR44 batteries.
Close the battery compartment. Make sure it is tightly closed.
As a fish hobbyist, it is imperative that you have an understanding of the water parameters that affect fish health, as well as the importance of water testing. Water testing cues you to what's happening in the system at any given time.
Often overlooked, pH may well be one of the most critical parameters in a healthy system. Maintaining the right pH range - 8.3-8.5 in marine systems - has a natural antiseptic effect, helping fish resist illness and coral calcify faster.
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