In front of the temple is a small roofless structure called the Purgatorium, which contained a tank of sacred water from the Nile. Like many Pompeiian buildings, its decoration is an eclectic mixture of styles and media. Around the top is a frieze of figures in Egyptian costumes, painted in the static, frontal, rigid style typical of Egyptian painting. On the sides of the building are stucco shallow reliefs in contemporary Greek style with mythological subject matter, idealized nudes, and flowing draperies. The front is painted with thin swags of leaves and flowers, which is very characteristic of the Pompeiian style of painting.