Protodermis purification was a process performed in Ga-Metru to remove impurities from liquid protodermis so that it could be used in the making of Kanoka disks. Liquid protodermis was drawn from the sea into the Great Temple. Here a special group of Ga-Matoran waited to begin purification work. While some read ancient passages calling on the Great Spirit Mata Nui for aid and protection, others supervised the rapid heating and cooling needed to cleanse the liquid. Once this was done, the liquid protodermis lost its silver color and became a clear fluid with a bluish tinge.
A device called a protodermis separation tank was used in the purification process. A model of it was kept in one of Vhisola's classrooms.
Ga-Matoran were constantly working and inventing ways to perfect purification methods. They kept models of the best inventions in their labs for inspiration.
Protodermis labs were science facilities in Ga-Metru schools devoted to finding more efficient ways to use and purify liquid protodermis, as well as to the continuing effort to synthesize energized protodermis.
Ga-Metru was full of teachers and students, and those who were particularly skilled were able to be part of the protodermis purification process.