Okay thx for the key-word. I red something about the matter and what i can get from it, is that my current code does render both water and cube because i do not let the cube write to the depth buffer and thus the water is not occluded (And translucent and opaque triangles seem to be handled differently since the opaque blocks are never occluded by the cube). But still I do not sort the alpha triangles correctly so that in the current state water is rendered over the cube but does blend in a bit with the cubes color. Is that somewhere near the truth?