Xerxes fiberglass tanks from Rain Ranchers are below ground tanks that range from 600 to 50,000 gallons. As communities, businesses and industries become increasingly accountable to meet LEED and other environmental requirements that require safe, design-proven storage, Xerxes is in the forefront with innovative answers. When considering the options in customized systems for water storage, facility designers and owners look for a long-term, structurally strong, water tight and cost effective solutions. That is exactly what the Xerxes fiberglass tank offers.