Porcellionides pruinosus ‘Powder Blue’, often called Powder Blue or Powdery Blue Isopods, are a hardy species of isopod and produce quickly once established. Powder Blue Isopods make a great clean up crew in a bioactive setup or naturalistic vivarium. They are large, active, and very colorful. This species is also super fast! These isopods appear grey when immature. They then take on a purplish hue before maturity, then appear a steel blue color when mature.