We highly recommend this air pump for emergency back-up air in aquarium, small tanks, and small ponds. The pump is designed to run continuously on 110V power. When the power shuts off, the pump automatically switches over to battery back-up and continues to run until power is turned back on. It features two modes of back-up operation: Hi - runs 14 hours continuously on full battery mode; Low - runs 28 hours on intermittent mode where the pump is on for 50 seconds then of for 50 seconds. Utilizes a 66v rechargeable battery (included), which is easily accessible. Two 3/16" outlets provide 0.15 cfm of air at 30" of water depth.