Conductivity meters, dissolved solids meters, and resistivity meters are analytical instruments that measure the conductivity, dissolved solids, and/or resistivity of a liquid sample.
Dissolved CO2 instruments are analytical devices that measure the amount of carbon dioxide (CO2) dissolved in a liquid sample such as water. They typically include a submerged probe that is covered by a thin organic membrane.
Turbidity instruments measure the average volume of light scattering over a defined angular range. Both particle size and concentration of suspended solids as well as dissolved solids can affect the reading.