A technique was developed to evaluate alternative support systems to test tubes used in the standard most probable number technique, for simultaneous isolation and enumeration of cyanobacteria. Five different support systems were tested for their suitability in terms of accuracy, sensitivity, economics and ease of handling. PCR plates with 96 wells and carrying capacity of 300 microL per well were found to be most sensitive, besides being cost- and time-effective. This technique can also be useful for isolation of cyanobacteria, due to immobilization of colonies in the gel matrix and storage of samples at room temperature, without loss of viability for 5-6 weeks. This technique can help to process large sample size with ease--both for enumeration and isolation and can be extended for enumeration of other microorganisms from diverse sources.