Category talk:Water quality indicators

To do

 * KH (hardness)
 * Settleable solids
 * Electrical conductivity test
 * Dissolved oxygen
 * KH (hardness)
 * Settleable solids
 * Nitrate concentration
 * Nitrite concentration
 * Phosphate concentration
 * Sulphate concentration
 * Conductivity (electrical measurement of ions in water)