GARVEE Water Quality Tester, GARVEE TDS Meter, EC Meter & Temperature Meter 3 in 1, 0-9990ppm, Ideal Water Test Meter for Drinking Water, Aquariums, etc.

We wanted a water tester to test/compare TDS of Brita filter vs. under-sink kdf/carbon filter vs. RO filter. Our house is in an area with a mining history and where all water comes from municipal wells. This little guy seems to have fit the bill perfectly. Its cost is relatively low and it definitely reads a difference for the various filters. Both carbon-based filters remove little tds (the filtered water registers hundreds of ppm tds). The RO system registers near 0ppm. So …. RO it is. We hate the water waste associated with RO (5-6gals per 1filtered gallon) so we capture the waste water in buckets and use it to flush toilets, clean/mop or water plants.We don’t use this device frequently. We have not used the other functions. I don’t know how long the battery will last. I would recommend it.

I requested the MERXENG Professional TDS Meter for Accurate Water Testing to monitor my aquarium dissolved solids contents since you can't see them with the naked eye. I can't refute the readings so am assuming the readings are accurate and I can use them to spot any trends that may occur. So far, it has been reading the aquarium water dissolved solids at a consistent level. I recommend the product, especially at this price point.