I visit the Qabr of my mother every week and I throw water on her Qabr.

Answer

The act of pouring water on the Qabr is prohibited for the following reasons: 1) It never was the practice of Rasulullah (Sallallahu alayhi wasallam), the Sahaabah and of the Salafus Saaliheen. It is an innovation (bid’ah). 2) It is a practice of the kuffaar. 3) It is a futile practice devoid of any merit.

The inmate of the Qabr does not derive any benefit from this practice. Make Dua, recite the Qur’aan Majeed and give charity for the Isaal-e-Thawaab of your marhoomah mother.