Tanks are blocks designed for holding liquid. One tank block can hold up to 16 buckets of liquid. Tanks placed next to each other will not be connected, however while placed on top of each other, they will link together and function as a single, larger tank.
Liquids transported by Waterproof Pipes are deposited into the tank. Liquids can be extracted from the Tank using Wooden Waterproof Pipes connected to an Engine. Liquids can also be exchanged with a Bucket.
When filling stacked Tanks with waterproof pipes, they will fill the entire stack, regardless of the pipe's location relative to the top or bottom of the stack. However, when extracting fluids from the Tank using Wooden Waterproof Pipes, the pipe will only extract down to the Tank it is attached to, so the extracting pipe should be attached to the bottom of the stack if you wish to extract all of the liquid.
Tanks are useful when you want to store the fluids. They can hold mass amounts making them a good source of Oil and Water for Combustion Engine's.