Must ablution be repeated if impurity is found in the water after use, and the water volume was less than two qullahs or reduced from two qullahs by use?

Primary text

If one performed ablution using a large quantity of water which subsequently changed due to impurity, and it is known that the impurity occurred before the ablution, or if the water was less than two qullahs or diminished from two qullahs through use, the ablution must be repeated. This is established because the default status of the water is considered diminished (or impure, necessitating repetition of the act performed with it).