APEC TDS Meter Digital Water Quality TDS Test Kit Meter with Carrying Case, 0 to 1999 ppm Measurement Range, 1 ppm Resolution, +/- 2% Readout Accuracy

Out of packaging it didn't work. Turned out to be a defective battery. Replaced battery and it works great for testing my reverse osmosis system.

Make sure to test water of equal temperatures when comparing them.For fun I tested hot and cold, expecting the same results, but to my surprise, they were markedly different. I was initially confused as to how my hot water (104.2 degrees) would read 109 and my cold water (64.4 degrees) read 62, but figured out it was in fact due to the difference in temperature and nothing else. After setting a glass of each on the counter and letting them both equalize to room temp, they bold read 68 TDS.I would venture a guess that the increased temp makes the ions move more quickly, causing the meter to miss read the levels. I would like to know what temp is ideal for the most accurate reading, but, at least I do know you can make an apples to apples comparison if the temps are the same.Also, did some testing on my standard Brita filter. Tap water was 68, one pass 28, second 19, third 14, fourth 12, fifth 12 again, sixth... you guessed it, 12 again. Thought it was interesting, and maybe someone else will as well.Easy to use, easy to read, and as far as I can tell it seems to be accurate but lack the instrumentation to verify that. I just know it read levels out as expected (numbers went down with filtration each time) and that was good enough for me!

Everything tests out at 30-37 ppm. I did not believe that all our drinking water was that low! So.....I bought some 300+ ppm control and it tested out fine. I then made my own 1000+ ppm control and it tested fine. I will add to this review as I am going to compare numbers from a different tester using controls that I know. So far so good A nifty little tester. I give 4 stars because I would like to see an appropriate vial of control INCLUDED in the packaging. Very low cost and the buyer could see the calibration of , say, 1000 ppm and compare to their readings of household drinking water and stored emergency water. Overall I would recommend this to buyers.

This tester works fairly well at just testing how much particulate is in your water. It obviously doesn't tell you whats in the water, but if it tests super low near zero, then you are drinking very clean and most-likely reverse osmosis water. I tested the water all around my work one day and now know which areas are safe for drinking. I let my close friends know which water is safer for drinking and they appreciated that. Some water tested very high, like 200 ppm which is probably full of things that will kill you. I enjoy testing all my water and filters and this tester makes it easy to do.

Muy bien

Definitely works. I tested my tap water and we had a whopping 496ppm! I knew it was bad but not that bad! So nervously tested my RO water system a bit earlier than I should have (I was still emptying out the first tank) and it came down to 28ppm! After a full water cycle it was down to 22 in the RO filtered water, I was so happy my RO system was doing excellent work (also from APEC). Now my relatives want me to test the water at their place lol.

Very easy to use. The only reason I gave 4 star is it doesn’t give you a list of what the TDS amounts mean. I had to look it up on line

I really don't know about this Tester, sometimes it shows right numbers and sometimes not. I was trying to use it for a while and now it just sits on the side. Maybe I just don't know how to use it.