Auto-focculation does not occur in all micro-algae species and can be slow and unreliable (Schenk et al. 2008). Flocculation can be induced by chemicals, both inorganic and organic, or by microorganisms; but flocculants may be algae species-specific and recovery and recycling of the flocculants can be problematic (Mohn 1988; Molina Grima et al. 2003; Oswald 1988; Shen et al. 2009). The shape, size and composition of flocs can be very diverse depending on micro-algal species and floccu lant (Jago et al. 2007). An ideal flocculant should be inexpensive, nontoxic and effective in low concentra tions (Molina Grima et al. 2003) and it should also preferably be derived from non-fossil fuel sources, be sustainable and renewable