Using a TDS meter to measure water quality
If you've had a few issues with how your water tastes, it's perhaps because there's too much of a certain kind of mineral or nitrate impacting the water quality.
The principal constituents found in water are usually calcium, magnesium, sodium, and potassium cations and carbonate, hydrogen carbonate, chloride, sulfate, and nitrate anions.
We understand if you need to go and google exactly what a few of those things are. But the short of it is that if you have too many dissolved in your water, it will taste bad and worst, harm your health. According to the World Health Organisation, unhealthy water can be carcinogenic, contribute to coronary disease and increased mortality rates when TDS levels are too high.
So we understand why you might be in the market for a TDS tester. And here's one of the best: While you can use a water test kit to ascertain the presence of such things, a Total Dissolved Solids meter (TDS) will help you correctly determine the extent of your probably and measure the effectiveness of any corrective measures you take (such as installing a reverse osmosis filtration system).
A TDS meter is simple to use and most of them will give you accurate results which will allow you to make decisions on how to treat your water e.g. install a filter.
A TDS meter works by estimating the number of TDS by determining the electrical conductivity of the sample by passing a small current through it.
This is because the ions, minerals and other particles present give off an electrical charge which can be measured.
The digital meter measures in parts per million (PPM). A reading of 1 ppm indicates 1 milligram of dissolved solids per kilogram of water.
So what then is a good or bad TDS reading?
The World Health Organization which is oft considered the expert authority on such matters suggests the following assessment guide:
- TDS level less than 300 mg/liter is excellent
- Between 300 and 600 mg/liter is good
- Between 600-900 is fair
- Between 900 – 1200 is poor
- More than 1200 mg/liter is utterly unacceptable.
This is not the real measure of health though. If we are talking about public safety then the minerals and metals present themselves such as nitrates are subject to their own guidelines.
If you are testing the TDS level after you have installed a filtration in your home, make sure you take a sample before you install the meter and write it down. This way you will be able to compare the readings and satisfy yourself that your water quality has improved.
Fish tanks and measuring TDS
You can also use a TDS measure to determine how suitable the water in your fish aquarium is.Gotta keep those guppies healthy!
Fish release lots of nitrates into the water and algae is constantly keen to grow and take over a tank.
A quick check with a meter allows you to consider whether to add freshwater or to completely clean out the fish tank.
TDS meters may be used with salt water and fresh water tanks.
It's pretty simple to use a digital TDS meter in an aquarium - you can simply dip the electrode into the water's surface or you can take a sample and then test that.
TDS level for a fish tank is ideally the range between 130 and 195 ppm.
TDS level for a fish tank is ideally the range between 130 and 195 ppm.
How to calibrate a digital TDS meter
Just like when using a pH meter for brewing beer, it's really important to properly calibrate the TDS meter before use. Proper calibration will ensure that the meter takes an accurate reading.
Here's a sweet video tutorial on using calibration solutions.
Automatic Temperature Control is quite a desirable function for TDS meters. It accounts for variations in temperature that can affect the calculation of the total dissolved solids. If you've studied a little bit of chemistry, you'll be keenly aware of how temperature can affect chemical reactions!
You may also wish to consider the pH level of the water as well.
Here's a sweet video tutorial on using calibration solutions.
Does a TDS meter need Automatic Temperature Control (ATC)?
Automatic Temperature Control is quite a desirable function for TDS meters. It accounts for variations in temperature that can affect the calculation of the total dissolved solids. If you've studied a little bit of chemistry, you'll be keenly aware of how temperature can affect chemical reactions!
You may also wish to consider the pH level of the water as well.