Tank and lagoon cover systems from Geomembrane Technologies control odor and temperature and block sunlight to control algae growth and chlorine loss. Their high-strength, UV-protected coated fabric is tensioned across low-profile aluminum arches that span tank and lagoon openings. The cover is secure, yet detaches easily for access for inspection or maintenance. Rainwater runs to the tank perimeter. The fabric is durable and resistant to wastewater environments. Aluminum hatches can be located in the walkways for inspection or sampling, or fabric hatches can be located in the covers. 506/452-7304; www.gticovers.com.