As there is no accurate method other than to test out the TDS to confirm replacing the DI cartridge from TAP WATER FILTER than the one which TWP suggests to check visually the color of the DI Cartridge.
Those who are using the TWP will know how difficult is to identify the color of the resins when it is due for replacement.
So bought this TDS meter which comes with a soft leather casing and a very basic simple instructions manual.
The TDS meter is a pocket sized ABS case and is powered by a 3V CR2032 cell battery. It claims that the battery life can take more than 1000 meausrements but then who bother to keep track. Right?
This meter has a 4-digit LCD display screen and it can detects range from 0 to 1999 ppm. It also has an auto shut-off feature for those absent minded reefers and is a idiot proof electronic TDS meter.
Calibration of the TDS meter is by using the TDS 800ppm calibration solution and it doesn't comes with the meter. Got to pay for it!
Comments: Simple and inexpensive piece of test equipment for those who are using RO/DI water as this TDS meter sets you poorer by S$65 inclusive of shipping.