3V mini air diaphragm DC pump for diffusing air in fish tank for aeration

Demonstration of a tiny diaphragm DC pump for diffusing air in a fish tank. We use two different power supplies. A 3V input from a variable power supply and a 5V input from a USB charger. The second option for a power supply is low cost and simple. In fact, you likely have one of these laying around your house you could use.