How should I deal with the whispers of the devil with regard to ablution and purity?
Whispers in ablution are from the devil, and so you should take refuge in Allah from the devil`s evil suggestions that aim to distort the religion. Thus, once an organ is completely pure, don`t question its purity since having whispers doesn`t mean that the purity is invalid as it has already been established.
What is the ruling on eating from one`s Udhiyah?
In the Name of Allah, and may peace and blessings be upon our Master, the Messenger of Allah.
The Udhiyah (sacrificial offering) is divided into two categories: the vowed sacrifice (Al-Mandhurah) and the voluntary sacrifice (Al-Tatawwu').
First: The Vowed Sacrifice (Al-Mandhurah)
This refers to a sacrifice that has become strictly obligatory due to a formal vow (Nadr). It is completely impermissible for the person offering it, or any members of their family whom they are financially obligated to maintain, to eat any of its meat or fat. Furthermore, it is unlawful for them to personally benefit from its hide, wool, or any other part of it. If they happen to eat any portion of it, the offerer is legally obligated to give an equivalent amount of meat or its monetary value to charity. (As noted in Tuhfat al-Muhtaj by Imam Ibn Hajar al-Haytami,Vol. 9/P.364).
Second: The Voluntary Sacrifice (Al-Tatawwu’)
This is a recommended, non-obligatory sacrifice. The person offering it is fully permitted to eat from its meat, distribute portions as charity to the poor, and give pieces as gifts to those who are well-off. However, it remains a mandatory requirement to donate at least a minor portion of it to charity; this should not be less than approximately half a kilogram of raw, uncooked meat. And Allah the Almighty Knows Best.
What is the ruling on water that contains ornamental fish — does it become impure on account of their waste?
All praise is due to Allah, and peace and blessings be upon our master the Messenger of Allah ﷺ.
The water in a pond containing ornamental fish is pure so long as it has not been altered, for a small amount of fish waste (rawth) is pardoned and overlooked — provided it does not change the water.
It is stated in Ḥāshiyat al-Jamal ʿalā Sharḥ al-Manhaj (Vol.1/P.178): "A small amount of hair from a non-edible animal is pardoned, as is a small amount of hair from a riding animal — on account of the hardship involved in avoiding it — and likewise a small amount of fish waste is pardoned, unless it alters the water." And Allah the Almighty knows best.
Is it required for a discerning child to make the intention at night if they wish to fast?
If a discerning child wishes to fast during Ramadan, they must make the intention at night because intention is one of the pillars of fasting, even though fasting is not obligatory for them.