How to use SetWaterCell better?

So, I'd like to be able to spawn water like you spawn a brick. Let's say I want to spawn water at x=1 y=1 z=5 and I want the water to be sized x=2 y=2 z=2. How would I do this? I can spawn the water where I want with

Workspace.Terrain:SetWaterCell( 1, 1, 5, 0, 0 )

but I can't choose how much water to put there, only 1 block of it.