HM Digital Meters HMDTDS3 3 Handheld TDS Meter

If you take water seriously this is a good piece of kit for your toolkit. This has told me how bad my tap water is, 375 TDS or ppm, parts per million, or 375 mg of junk per litre in my tap water. I have now got fitted reverse osmosis under my sink and my new drinking water has 10mg of minerals per litre and no junk, all because I purchased this little gadget. My skin is better, my hair. I reccomend this product 100%

Good product. Worked as expected

Fonctionne correctement, que ce soit pour le % de sel ou la température.

Super Ware, danke gerne wieder!!!!

Easy to use, and now I can accurately and quickly check the status of my aquariums' water, without having to fiddle around every day with little glass test tubes and drops of test fluid. I now do that once or twice a week.My reason for 4 stars? The thermometer is not particularly accurate - out by one full degree when checked against three other thermometers which all give the same readings. That may not seem like a huge problem, but it can wipe out a tank full of fish or shrimp if the temperature is too high.

Works great!!! No complaints for the money.

I love this thing. I use it all the time to see the dissolved solids content in all different waters...

Good little meter for under 30 bucks. Cannot go wrong with that price. Have used it only a handful of times and do not foresee any drawbacks with it. I do need to verify the calibration soon tho just for peace of mind.

It is easy to use, but it only gives the temperature in Celsius, and you have to convert to Fahrenheit.

I just bought one of these units earlier today as my old unit had failed months ago and I noticed that my plants were having some difficulties with their growth. So, yeah, I paid a good bit more than it is being sold here but then again my plants were having troubles. So after some serious changes to my hydroponics system for my lettuce and tomato plants I hope to be seeing some good changes over the new week or so... I also found that I needed to implement some minor water cooling to my reservoir as well as this has a nice temperature meter built in as well. Water should be maintained at 75degF.Right now I'm only running a 10gallon system but the way I have it setup I'm able to grow 16 Lettuce plants and 1 tomato plant.I did have to re-calibrate the meter as soon as I got it as it was not reading any were it was supposed to, It was off by 140ppm. it was reading 860 when it should have been reading 1000, I was using some 1k sodium solution that I got at my local hydroponics store (30 min drive... not really local....)The temp sensor in it seems pretty accurate as I tested it on some water that I left a thermometer in and left to come to room temp and tested the unit and then tested it again after leaving the water in the fridge all morning. It was pretty much spot on.If I come across and problems I will adjust my review but this unit does come with a nice 3 year warranty and typically TDS meters will last a good 3-4 years without issue and can last 7+ years with low use.Things to keep in mind for testing:RO (reverse osmosis) water filtration system:The difference from your tap water to RO water should not exceed 90% IMO. Typically once I get to 90% I will go ahead and replace the filters. To come to this figure simply test your tap water from the faucet write that reading down and then take another reading from water taken fro the RO system. Simply divide the numbers and you will have your percentage. subtract that number from 100 and that will give you the efficiency level of your RO system.When testing for your hydroponics system you will want to keep a note pad so that you can keep track of your numbers so you don't forget them...Remember to test your water that you are using first before adding anything to it... Write that number down. I just like having my base numbers available...Now adjust your PH of that water and test again, write that number down.Now to get the proper PPM of nutrients in your system you simply add the PPM value you want your plants to have (typically 1200 for nutrients for general growth and as little as 600 for seedlings) to your prior number you got from your water/ph adjustment. Once you have those values.Now write down what your total value is. This is about the amount you will need to maintain the system at.other calculations:Seeing as you have the PPM value of your base water and your PH adjusted water you should know how much 1cc affects 1 gallon of water. You will want to figure this number out so that if you find you need to adjust your PH again you will be able to know how it will affect your PPM value and be able to adjust the numbers accordingly as to what your final total PPM will need to be with your nutrients in the system.Hope this helps you guys to understand the importance of such a meter..If I have any problems with this unit I will come back to adjust my review.