Biorb flow 15l black a beautifully designed aquarium perfect for beginner or expert fish keeperr the flow features reef ones proven filtration system which draws water and waste from the bottom of the aquarium for maximum efficiencyr the flow is made from acrylic rather than glass due to the fact it is approximately 10 times stronger than glass and is noticeably clearer acrylic also retains heat almost twice as well as glassr the biorb flow features a high quality led light unit with a con