Dissolved Oxygen

Dissolved oxygen, or DO, is the amount of oxygen dissolved in water. Dissolved oxygen can enter the water from the air (aeration), from plants (photosynthesis), or it can be introduced as part of a treatment process to remove certain contaminants. Higher levels of dissolved oxygen in water can cause it to be corrosive, especially to metallic surfaces.

Dissolved Solids

As water tends to dissolve materials it comes into contact with, it can contain a variety of dissolved solids. Some materials can cause adverse affects to human health, such as arsenic, barium, lead, mercury, and silver; while others have more of an affect on the ascetic qualities of water, such as iron and manganese. The level of solids in water is referred to as Total Dissolved Solids or TDS. Water with higher levels of solids can have problems with taste, odor, hardness, corrosion, and buildup.

Electrical Conductivity

Electrical conductivity is a physical characteristic that is used to indicate the level of TDS in water. Water with fewer dissolved solids will not conduct electricity as easily as water with higher levels of dissolved solids.