Review on KEDSUM Battery Aquarium Air Pump: Ultra-Quiet Rechargeable Fish Aerator with Dual Outlets - Ideal for Fish Tanks, Outdoor Fishing, Fish Transportation, and Power Outages by Ryan Gilliam

We got this right before the recent winter storm in the Houston area that was knocking everybody's power out. It was perfect to keep air going for our 55 gallon tank. We just charged it before hand (we used electric in the house, but since it's USB you could also charge it in your vehicle), set it up with 2 long bubble stones and plugged it in to electric, set the mode appropriately and when the power went out it automatically switched to the internal battery. It comes with plenty on long tubing, 2 check valves (defintely used those) and 4 small bubble stones if needed. Loved it! We may end up getting a second one to run our 2 10-gallon aquariums once they are stocked.