Studies have concentrated, almost exclusively, on the role of bacteria and fungi in the
degradation of dyes [I]. Limited number of studies are available on biological treatment
by algal species in spite of their ubiquitous distribution and their central role in the
fixation and turnover of carbon and other nutrient elements [27]. Algae has a high surface
area to volume ratio imparting significant potential for sorption and has been recognized
with respect to the persistent organochlorine compounds [28,29]. It is therefore
appropriate to study the role of algae in removing dyes because they are the natural
habitants of oxidation pond of wastewater treatment plants. Algal species of Spil-ogyl-a
has been selected in the present study because it is one of the dominant green alga found
in the oxidation ponds of wastewater treatment plants in India. The objective of the
present study is to investigate removal of colour of two azo dyes, direct red 28 and
reactive red 2 by Spil-og~rasp . in viable form.