After few weeks of grooming, the two full red males have turned into beautiful fishes. The males' colour still remain orangy red but finnages are great. I guess this is the trait of YaikSin's full red guppy.
In order to have a better colouration, I've decided to add a few virgin full red females from Y618 offspring to try for an outcross. Wish me success !
Update of YaikSin's albino full red guppy after one month of grooming.