The Advanced Hang On Back (HOB) Refugium Box Pro Series in Medium is a vital filtration and habitat enhancement device designed for saltwater aquariums of 10 to 30 gallons. It serves as an essential refugium, providing a separate environment for macro-algae growth and beneficial micro-organisms such as copepods and amphipods, which naturally improve water quality and reduce nutrient levels in the main tank. Featuring a robust hang-on design with integrated support systems, this model includes a powerful Fiji Flow 300DC Nano DC pump, offering precise control over water flow and feed mode functionality to minimize stress during feeding times. The spacious chamber accommodates various needs such as algae cultivation or fish acclimation, while its full cast acrylic construction ensures durability and longevity.