User blog:Tobuscus Jr./Infininte Water Bug

The objects highlighted in bold are important, and are not to be neglected.

The infinite water glitch is a useful one when it comes to filling or refilling a large body of water.

To get started, build a water tank at least 25 blocks up 49 blocks across, and fill it with water. Next, wire a lever/switch to an actuator placed on a single block on the floor of the tank. When the water tank is completely full, flip the switch. If you built it correctly, water will flow out the bottom without loss of water in the tank. If built too small, the water will empty from the tank and you will have to start all over.

I give full credit to the YouTuber who taught me how to do this, Yrimir. (https://www.youtube.com/user/Yrimir)