How The The Winx Got Sirenix
The hadas need to find the Gem of Self-Confidence, Empathy and Courage within one lunar cycle in the oceans that are all over the magic dimension, o they would lose their powers forever. After that, they needed to activate the fuente of Sirenix in Lake Roccaluce. Then the fairies' Sirenix boxes will appear along with their Sirenix Guardians, who combine their powers to open the portal to the Infinite Ocean. Finally, Omnia, the Supreme Guardian of Sirenix will appear with the portal to the Infinite Ocean which the hadas needed to cruzar, cruz into and they became Sirenix fairies.
The Witches can't be allowed to acquire Sirenix por the Sirenix Quest, as the Trix, the only Witches known to have acquired Sirenix, obtained it after Tritannus estola it from Daphne, a Sirenix Fairy, and gave it to them. In order to acquire it they must open the Sirenix book which the Winx have in their possession and complete the Sirenix quest.