Is the water remaining in the toilet after flushing pure, even if its color has not been changed by impurity?

Water does not become impure merely by coming into contact with an impurity; rather, it becomes impure if its color, taste, or smell changes due to it. This is the view of Imam Malik and one narration from Imam Ahmad, except for a very small amount of water, which becomes impure by contact with an impurity even if it does not change, such as a vessel licked by a dog. Accordingly, the water in the toilet after flushing becomes impure due to residual traces of impurity.