Assessing Nutrient Deficiencies
The Challenge AER-200 respirometer system is ideally suited for assessing the occurrence of nutrient deficiencies as illustrated in the figure below. In this case various amounts of a mixture of nutrients and trace minerals were added to different respirometer vessels that received 25 mL of wastewater plus seed organisms. The resulting oxygen uptake reactions show increasing oxygen uptake with additional nutrients and minerals until adequate concentrations were reached. Additional tests revealed that the sample was deficient in calcium. These tests also show that several hours of incubation may be required to show the full effect of a nutrient deficiency.