HM Digital unisex adult Pocket science lab ph meters, Brown, Without Digital Thermometer US

It is very simple to use. Here are the instructions from the packaging:1. Remove the protective cap2. Turn the TDS meter on. The on/off switch is one of the buttons clearly visible on the front of the device below the digital readout.3. Immerse the meter into the water / solution up to the maximum immersion level (2 inches)4. Wait until the display stabilizes. This takes about 10-30 seconds. If you can't read it while this is happening, then push the "hold" button and it will hold the reading after you take it out of the water.Like many others I bought this to test the effectiveness of our reverse osmosis water purification system. Worked for that job perfectly and very easily. I first used it in late Aug 2014 when we hooked up our new system. The tap water was at 118 ppm, the water from a brita pitcher was at 68 ppm, and the RO produced water was 30 ppm. A few days later I did it again and got nearly identical numbers (120, 74, 32). Never touched it again until today, 3/8/15 when the tap measured 119 ppm and the RO-treated water was at 8 ppm. Maybe the filter performance improved after they were used a little bit, not sure. Regardless, this device is very simple, super accurate, and really cheap--what more can you ask for?

I was a bit skeptical, to be honest. But this simple and inexpensive tds meter seems to work. Out of the box, I stuck it in distilled water. It read 1 ppm - accurately, in other words. Water from my tap (from a deep well) read 190 ppm; the same water from a brita filter read 95 ppm; and my Crystal Geyser water from a gallon jug read 65 ppm.I got this to get a general idea of the water quality for my espresso machine, shooting for 75 to 100 ppm to minimize scaling but still have sufficient dissolved solids/minerals for good extraction and to trigger the water level sensor on my dual boiler setup. I now mix the CG jugged water and brita water to hit my targeted range, and check with this meter. Which is easy to do: press the on/off button, stick the business end of the sensor about one inch into the water reservoir on my espresso machine, press the 'hold' button, remove to read, shut it off.Is it accurate enough for mission critical work? Who knows. It does seem consistent enough to help me monitor water quality for my purposes, and for the price, that's plenty good enough.

Not sure what to expect from a 20 dollar tps meter, but it performs as advertised... I think... Most of the time, at least.I bought the 342 ppm calibration liquid to double check this meter, I never get readings that are more than 5-10 ppm off. It really is always in calibration and it comes that way from the factory. For me that's accurate enough. But, there are times when I get readings that are off by 50-60 ppm just by retesting the same water after 5 second (it's not from off gassing, this happens on water fresh from my tap AND water in my aquarium that's). Then there are times when I test 4 or 5 times in a row and get readings with only 2ppm variation.So take this info/review for whatever you think it's worth. This meter WILL come factory calibrated and it almost always gives you relatively accurate readings regardless of water temperature, but it won't ALWAYS give you dead on ppm readings

I have been using this unit for a year now and it is a great help in determining when to change water filters. This pen tester is so easy to use and it is instantaneous. It has also proven to me that both distilled water and reverse osmosis systems are by far... by FAR the best ways to filter water.The tap water I use is typically 072 ppm in the suburbs of Boston. Using the Aquasana AQ-4000W table top unit, I found that the unit initially was around 068 ppm for the first couple of months and is now at 083 ppm. I was surprised at that number since the filters are very large and it was showing me that it was leaving material behind in the filtered water and it became progressively worse over time. That means that the water is now coming out with more dissolved solids than my tap water originally had... wtf is that?Distilled water consistently comes out at about 005 ppm as does my reverse osmosis system. The meter comes in handy for the reverse osmosis system to tell me when to change the filters. It also shows me that if I use the reverse osmosis water as the pre-filtered for my distiller then the reading comes out to the lowest reading of 001 ppm and the water tastes amazing.

This TDS meter is perfect for testing your reverse osmosis water to ensure that the membrane is still working properly. I've had this unit for a number of years now, and I use it every 6 months for this purpose when I change the sediment and carbon filters in my RO system. The membrane cartridge in an RO system is the most expensive part to replace, and most of them are rated to last 2-5 years. But how do you know when it's time to replace the membrane? Do you play it safe and just replace it at two years, or do you run "fast and loose" and milk a full 5 years out of it? Well, a TDS meter will tell you exactly how well your membrane is performing. If you replace the sediment and carbon filters every 6 months like you're supposed to, you extend the life of your expensive membrane cartridge. And 5 years is *not* the upper limit. I got nearly 7 years out of my last one, because I use a TDS meter to test it every 6 months at filter-change time. There is no reason to replace the membrane if it can still remove 75-80% of the dissolved solids in your tapwater. There are several good sites that explain the testing procedure in detail, and it's very easy.

Caused me to chase metrics and overdo water changes. Now my shrimp are dead. Fish are doing well though.

Muy fácil de usar, llegó en menos del tiempo indicado.Bastante funcional para el uso que le tengo pensado, que es casero/no industrial (aunque tal vez también funcione para eso, no lo sé).Se ve durable y resistente, de calidad aceptable.

I was anxious receiving as there was some positive review. Upon receiving the meter, opened up. To my disappointment, the meter does not work at all. Even after changing new batteries, the meter still does not work. Lost hope to such called budget priced meter

A nice meter, convenient, fast, apparently of good quality. I ordered it a few days ago after I had met an online report suggesting that local water is extremely hard (which, by the way, is not good for health). I bought exactly this model because of good accuracy, automatic temperature compensation, good reviews at Amazon.com, price discount, and because of the negative review here complaining about high sensitivity (!). High sensitivity is precisely what I was looking for. The meter showed 367 ppm in tap water, - very hard indeed and not suitable for human consumption. 295 ppm appeared after Brita filter, - so the Brita does remove some junk, but the water is still too hard. In distilled water the device showed 0 ppm (for such a delicate measurement, the electrodes and the cup should first be rinsed with distilled water, otherwise even faint residues from tap water could influence the result). Thus, now I can control the situation with drinking water. Such a monitoring is quite important to prevent health issues. If the water is very hard, drinking 2+ liters of it every day, as they recommend, will gradually ruin the body (likely causing problems with the joints, kidneys etc.) instead of providing health benefits. Yet another aspect is water pollution, the scale of which often correlates with water hardness. So, without a reliable TDS-meter people might risk their health, if they do not realize the water they drink is too hard.

Very good quality. I recommend.

Works very well