Weird acting water

I am trying to make a cave with a stream running through it, I followed a water tutorial “blender guru” made. I baked it, and the water is weird and cube like. It ignores the cave. The cave started out as a cylinder, I set the particle fluid thing for it to obstacle, shell. Any idea what is wrong?:confused:

well you didnt follow that unknown article as good , but we can only guess.