Grate

Use
A grate is a connector between a pipe system and fluid source blocks. It has to be placed near some fluid source blocks.

Grates can either remove fluid source blocks from the environment and put them into a connected pipe or place fluid source blocks coming in through a connected pipe in the anvironment. Which of these two options they do depends on the direction the pump pumps the fluid.

Building tanks for fluids is possible but it is very strongly recommend to build a roof on the top of the tank, otherwise it will flow over.