Abstract: A water analyzer having several electrodes of the type which normally interfere with one another. These electrodes include a first electrode which is an active measurement electrode which perturbs the solution in which it is used and a second electrode whose reading is affected by the operation of the first electrode. Accurate readings are provided by sequencing the operation of the electrodes so that they are not always operating at the same time. In addition, further correction of the readings is provided to compensate for the known error resulting from the operation of the active electrode or electrodes. Such electrodes read conditions such as pH, dissolved oxygen and conductivity.