Neptunian Rock is a natural dry reef rock sold by weight, specifically designed for aquarium use. These porous limestone rocks provide an ideal foundation for coral reef aquascapes and create essential biological filtration surfaces in marine aquarium setups. Key features: • Natural reef rock composition • Sold by weight (per kg) • Porous structure ideal for beneficial bacteria • Perfect for aquascaping • Provides natural habitat for marine life • Helps maintain water chemistry The rocks come in various natural shapes and sizes, allowing for creative aquascaping possibilities. Being dry rock means it is free from unwanted hitchhikers or pests that sometimes come with live rock. Before use, it's recommended to cure the rock by soaking it in saltwater for several weeks to establish beneficial bacterial colonies.