How much is a lot of water, and how much is a little?

There are two scenarios if impurity falls into water:

Scenario One: If one of its characteristics (color, smell, or taste) is altered by the impurity, it is definitively impure by consensus.

Scenario Two: If none of the water's characteristics are changed by the impurity, scholars differ on two approaches:

Approach One: Distinguishing between large and small quantities of water. This is the view of the Hanafis and Shafi'is, and the well-known position in the Hanbali school: - They differed on the criterion for distinguishing between small and large quantities. The Hanafis held that a large quantity is one where impurity falling on one side does not reach the other side. The Shafi'is and Hanbalis held that the limit is when the water reaches two qullatayn, which is approximately (307) liters, basing their argument on the hadith (definition): "If the water reaches two qullatayn, it does not carry impurity."

Approach Two: There is no distinction between small and large quantities of water, and water does not become impure unless it is altered by the impurity. This is one of the opinions in the Maliki school and a narration from Imam Ahmad, and it is the preponderant view, based on the hadith: "Indeed, water is pure, nothing makes it impure."

Summary: If the effect of impurity appears in water, it is impure. However, if the effect of impurity does not appear in it, the preponderant view is that it is pure, whether it is a small or large quantity.