Narrated to me by the Shaykh (Al-Mufid), may Allah سبحانه وتعالى support him, who said: Ahmad bin Muhammad bin Al-Hasan narrated to me, from his father, from Sa'd bin Abdullah, from Muhammad bin Isa, from Yasin Al-Basri, from Hariz bin Abdullah, from Abu Basir, from Abu Abdullah عليه السلام: Imam عليه السلام was asked about stagnant water in which animals urinate. Imam عليه السلام said: 'If the water changes, do not perform ablution with it. But if their urine does not change it, then perform ablution with it. The same applies to blood if it flows into the water or anything similar.'