Total dissolved solids (TDS) are essentially a measure of anything dissolved in water that is not an H2O molecule. Eg: Calcium, Magnesium, Potassium, Lead, Zinc, Arsenic etc. Total dissolved solids can affect your water quality, your health, your home plumbing system, and even daily tasks, such as cooking and cleaning. By measuring your water for TDS, you can better understand your water quality and how it affects your everyday life. Testing your water using a TDS Meter is the simplest way to measure the water hardness and make sure that you are drinking clean water. Akua beat TDS meter is an inexpensive and convenient digital tool to instantly check your overall water quality. TDS = Total Dissolved Solids. With the push of a button, the TDS can tell you your overall water purity level, which will be displayed on the screen in ppm (parts per million). The lower the TDS level, the purer the water. (The meter does not test for biological contaminants).