The Tunze Nanostream Rock 6025.250 is one of the accessories that make Tunze pumps so easy to work with. The Nanostream Rock is primarily used to hide Tunze Nanostream powerheads, but it can also be used to position a pump on the bottom of a tank. Made of white ceramic stone and suitable for fresh or saltwater applications. Works with the Tunze Turbelle Nanostream 6025 Pump, Tunze Turbelle Nanostream 6045 Pump and Tunze Turbelle Nanostream 6055 Pump.