Analytical methods for the automatic determination of micronutrients in seawater based on the TECHNICON Auto Analyzer (AAII) principles are described. The methods are adaptations and modifications of existing photometric methods already described in the literature. Automated methods are presented for the determination of the different forms of nitrogen available to plant life, namely nitrite, nitrate, ammonia and total nitrogen, as well as for phosphate-phosphorus and silicate-silicon. All these methods are in routine use by the Sea Fisheries Research Institute.