Each plant has its preferred solution concentration to facilitate the absorption process to the roots. Solution concentration is measured in EC, cF or TDS value. High EC values, meaning high nutrient concentration, may result in wilting and suppressed growth of plant. This must be monitored as frequently as possible because evaporation takes place in any environment that is warm and dry, so that remedial action can be taken.

The pH of nutrient solution decides the availability and absorption of nutrients by each species of plant. Every plant species has a preferred pH range in which it will grow best. Wrong pH of nutrient solution will result in retardation of growth and even death of the plant. Though commercially available nutrient solutions are balanced in pH, but when it is diluted with water from a different source, the pH may change from acceptable to unacceptable for the plant. Therefore, pH must be checked during the startup of a new crop, and then monitored at fix intervals up till harvest.