HM Digital DM-1 In-Line Dual TDS Monitor, 0-9990 ppm Range, +/- 2% Readout Accuracy,Blue & White

Works great. Does exactly what it was intended to do. No leaks.

There is no reason not to give this product the highest rating. The price was right, it does exactly what it is supposed to do and it is easy to install. The meter is simple to install; I have mine mounted with clamps right onto the side of the RO gland. Simply push the button for power and select, back and forth if you wish, the input water TDS or the output water reading. The display is easy to read and it turns off by itself. I personally like to stay in the habit of manually turning off equipment when not needed. I checked it with a professional meter and the readings were identical. It is so convenient to use, allowing frequent checks that will keep the water quality up. Don't be surprised, it is smaller than one would expect, but not a problem, its still easy to read from an arms length.

I could hardly believe how easy this instrument was to install. It must have taken me at least two minutes and it was up and running producing accurate results, I checked it with my handheld meter. The display is a little small but that's no big thing. Pun intended.😀 a great buy in my opinion.

This meter functions fairly well. If the two sensors don't have enough water around them in fitting they read low, so they need careful placement in T fittings. The meter output matches handheld conductivity and its inexpensive. My main issue is the low contrast LCD display that requires direct view and more than ambient light. The product concept is great and it's easy to switch from source water to RO.

I love this tds in line meter. I always know when I need to change my water filters now. It came with everything I needed to hook it up to my aquaticlife RO water lines. It gives a tds reading of the water before and after it runs through my RO filter.

Easy to hook up took 5 min tops. Have one probe on waste water and the other after the DI media. Takes the guess work out of when to change DI media!

a must have. this tells me my TDS out of the tap and after my DI unit (0 out tyvm!) :) make sure you install correctly. there is only 1 way to install them into the line to read correctly, so follow the directions! a must have for a reef tank ro/di unit!

It took literally 5 minutes to install this unit. I had no issues at all. My only concern is the accuracy but in all fairness I have this TDS monitor and a handheld TDS monitor. Both report different numbers so it's hard to tell which one is not accurate. My hand held unit reports between 14-18 TDS from the reverse osmosis faucet. This unit is reporting between 5-9 TDS on the 1/4" line that runs to the faucet. When I test my tap water from the normal kitchen sink faucet I get between 380-395 TDS with my hand held tester and betwee 350-375 with this unit. The only variable in both measurements are the faucets. Unless my reverse osmosis faucet is leaching about 9 TDS into my water then there is obviously a discrepancy somewhere. Same situation with my normal kitchen sink faucet. If I get access to a third TDS meter then I'll update this review with those numbers.