It is narrated from the words of Abu Huraira, may Allah be pleased with him, that the Prophet (peace and blessings of Allah be upon him) said:
“When one of you performs ablution, let him take water up his nose and blow it back out, and when he blows it out, let him do it an odd number of times.” This hadith was narrated to Abu Nu’aym in al-Mustahraj ala Sahih Muslim 475 and Musnad Humaidi 931.
Sheikh al-Albani called the hadith authentic. See Sahih al-jami ‘as-saghir 444.
444 ( صحيح )
إذا توضأ أحدكم فليجعل في أنفه ماء ثم لينتثر و إذا استنثر فليستنثر وترا
( أبو نعيم في المستخرج ) عن أبي هريرة .
Khadeeja