Rock this nice deserves the same treatment that corals do. Because this product is truly live we only ship it overnight. While it is packed to stay live and fresh for a minimum of 48 hours, by shipping it overnight we can target the shortest duration between our system and yours. The rock ships wrapped in paper, wet and in a reusable thermally protected box. Our beautiful Maricultured live rock starts off as MR Reef Saver dry rock before being deployed in the Florida Keys. After years of maturing in the ocean, the rock becomes full of beneficial life needed to start a thriving reef tank. Benefits include rapid cycling, greatly reduced \”ugly\” stage and the introduction of cool reef life such as sponges, corals and a diversity of beneficial bacteria. While Florida Keys rock is known for being quite pest free, there is always a chance of introducing unwanted animals or algae into your system.To combat this, MarcoRocks takes a three step approach. Once home in the MR greenhouse aquacultured systems, each rock is closely inspected to remove any undesirable marine life. It is then closely monitored and inspected once again prior to shipping. For best results we recommend using this live rock along with MarcoRocks dry Natural or Coralline rock.