Atlantic Water Gardens Water Matrix Block, 31.5 gallon Eco-Blox Water matrix blocks installed in lined excavations createweight-bearing underground water storage reservoirs With 96% void space, Atlantics Eco-Blox hold more water in a smaller volume, reducing the overall size of the basin Save labor, time and money on Pond-free, rainwater harvestingand storm water management installations versusgravel-filled reservoirs Eco-Blox lock together quickly and securely, easily supporting landscaping, pavers, gravel or sod for great design versatility Arrange modular blocks in any configuration and any number of levels to accommodate almost any basin Excellent for bog construction to create settling chambers below natural plantings of active bog filters