Phycocyanin is a pigment-protein complex from the light-harvesting phycobiliprotein family, along with allophycocyanin and phycoerythrin. It is an accessory pigment to chlorophyll. All phycobiliproteins are water-soluble, so they cannot exist within the membrane like carotenoids can. Instead, phycobiliproteins aggregate to form clusters that adher... Found on http://en.wikipedia.org/wiki/Phycocyanin
(from the article `algae`) ...Some green algae use carotenoids for harvesting photosynthetically active light, but the Dinophyceae and chromophyte algae almost always use ... Found on http://www.britannica.com/eb/a-z/p/61