Penn Plax Silent Air B10 Battery Operated Aquarium and Fishing Air Pump Manual On Off Switch Aerates Up to 29 Gallons Aquarium air pump runs on 2D batteries with continuous operation up to 96 hours. No electric is needed so pump can also be used for fishing. Pump will only operate when manually turned on and provides a constant supply of necessary oxygen to fish in an emergency. Aquarium air pump is safe to use in tanks up to 29 gallons. Air pump is also great option for transporting fish. Unit is compact and impact resistant. Air tubing and stone are included for easy set up. A check value is recommended but not included in the kit. Pump is safe for both freshwater and saltwater environments.