The purpose of airlocks

Airlocks in home brewing may seem small and unnecessary but they hold a true purpose.

1. To allow gas to escape and keep the inside of the tank at optimum pressure.

2. To keep contaminants from entering as the gas escapes. This is why there is water. It makes the escaping gas have to pass through the water instead of just drawing random particles in.

3. Allows the brewer to watch as the beer ferments. The gas bubbles allow us to actually monitor the progress of  our beer.

Just one of the many simple yet useful tools in home brewing.