What is the ruling on istibra' and how is it performed?
Istibra' (cleansing from urine) is recommended. It is for a person to ensure that nothing remains of urine in its passage before performing istinja'. Its method is: to clear the throat (or cough slightly), shake the penis (meaning to pass fingers along it to expel any remaining urine if needed), and walk a few steps to the extent that one thinks nothing of urine remains if walking is needed. Each person knows his own nature best. The preferred opinion is that this differs among people. The objective is for one to think that nothing remains in the urinary passage that he fears will exit later. And Allah the Almighty knows best.
What is the ruling on discharging one's zakāh obligation through the provision of a specific benefit (manfa‘ah) — such as performing a surgical operation for a patient, or providing housing to a tenant, and counting the value of this service as zakāh?
All praise is due to Allah, and peace and blessings be upon our master, the Messenger of Allah ﷺ.
It is obligatory to pay zakāh from the actual asset (‘ayn al-māl) upon which zakāh is due, except in the case of zakāh on trade goods ('urūḍ at-tijārah), which is paid based on their monetary value. In all cases, zakāh must be given in the form of tamlīk (a full transfer of ownership), based on the words of Allah, the Mighty and Majestic (which mean): "Zakāh expenditures are only for the poor and for the needy, and for those employed to collect [zakāh], and for bringing hearts together [for Islam], and for freeing captives [or slaves], and for those in debt, and for the cause of Allah, and for the [stranded] traveler — an obligation [imposed] by Allah. And Allah is Knowing and Wise" [at-Tawbah/60]. The letter "lām" (لِ) in this verse — as in "lil-fuqarā'" ("for the poor") — indicates possession/ownership (lām al-milk).
It is not permissible to fulfill one's zakāh obligation by providing a benefit or service (manfa‘ah) — such as housing, education, or medical treatment — in place of the zakāh itself. This is because zakāh must be paid as wealth (māl) that is transferred into the ownership of the poor recipient, whereas such services are intangible benefits that are not, in themselves, capable of being formally transferred in ownership (ghayr qābilah lit-tamlīk). And Allah, the Exalted, knows best.
If someone delays making up fasts for a year, can they give fidyah before performing qada?
Yes, it is permissible to give fidyah before making up the missed fasts (qada), because each is an independent obligation, and there is no required order between them.
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.