TDS Pens are capable of measuring the total dissolved solids in a body of water. By simply dipping the end of the meter, a TDS will instantly be shown. Such an instrument is incredibly important when keeping sensitive Caridina shrimp species. Tap water conditions are generally not ideal for keeping these shrimp, meaning RO water must be used and remineralised to suit the shrimp needs.
During water changes, the TDS pen is used for appropriate remineralisation of RO water so that shrimp can thrive.