First of all, the “true” gozzer is a tender maggot, not necessarily very big, stemming from a big blue-black fly that lay its eggs only in shadow-light or darkness. White or coloured, the gozzer is very valued by pretty fishes, colours like white and yellow seam to exercise a special attract on roaches and big breams. Tender and fragile, the gozzer retract itself from the moment you touch it, which is a way to distinguish itself. We can see that the gozzer is fresh thanks to its dark points: it’s the indication that it has a reserve of food. The gozzer can measure up to 2 cm, but it’s always smaller than the Damier. Well known by English people, this grub is stemming from a mat blue-black fly called Calliphora Vomitora.