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 permissible to divide one mudd of fidyah between two people?
No, it is not permissible to divide one mudd between two people, because it would not count as a full meal for either of them.
What is the ruling of Islamic Law on a fictitious marriage for the purpose of obtaining citizenship?
All praise is due to Allah, and peace and blessings be upon our master the Messenger of Allah ﷺ.
There is no such thing in our noble sharīʿah as a "nominal" or "fictitious" marriage or divorce. Marriage and divorce are among the sacred ordinances of Allah, and it is not permissible to manipulate them or use them as a stratagem to obtain worldly gains.
The foundational purpose of a marriage contract is the permanence and continuity of the relationship between the spouses — to establish a family, and to bring forth righteous offspring. So sacred is this bond that Allah the Almighty Himself described it as a solemn covenant (mīthāq ghalīẓ), saying {what means}: "And if you wish to replace one wife with another and you have given one of them a great amount of wealth, do not take any of it back. Would you take it in injustice and manifest sin? And how could you take it while you have gone in unto each other and they have taken from you a solemn covenant?" [Al-Nisāʾ/ 20–21]
Accordingly, it is not permissible to resort to manipulation and deception in contracts that Allah, Mighty and Majestic, has described as a "solemn covenant" — all for the sake of material and worldly benefit. Marriage is built upon permanence and does not admit of a fixed time limit. If a time limit is stipulated in the contract, the contract is rendered invalid by the consensus of the jurists. Similarly, marriage is impermissible when there exists a mutual, concealed intention to limit its duration — even if no time limit is explicitly mentioned in the contract — for this constitutes a form of unlawful circumvention of the sharīʿah. This is to say nothing of the lying and deception that such conduct involves, the prohibition of which needs no elaboration. Lying, deception, and fraud for the purpose of obtaining worldly gains are among the gravest of sins.
If, however, the marriage contract is first concluded in a valid sharʿī manner and then registered civilly, it is sound and fully valid. And Allah the Almighty knows best.
I have a date farm, and the dates come in different categories, and within each category there are different sizes. How is zakāh paid on the yield?
All praise is due to Allah, and peace and blessings be upon our master, the Messenger of Allah ﷺ.
If the yield reaches the niṣāb (the minimum threshold for zakāh to become obligatory) — which is five awsuq (plural of wasq), equivalent to (611) kg — then zakāh becomes obligatory upon it, at a rate of one-tenth ('ushr) if irrigated by rainwater (i.e., naturally, without the use of machinery), or one-twentieth (half of the 'ushr) if irrigated using machinery/equipment.
If the yield of dates consists of different varieties, then zakāh should be paid from each variety according to its respective proportion. If this proves difficult, it is permissible to pay from a medium-quality variety [representative of the average].
It is stated in Ḥāshiyatā Qulyūbī wa ‘Umayrah (Vol.2/P.22): "Different varieties are combined together [for the purpose of calculating the niṣāb] — such as the various types of dates, the various types of raisins, and so on — and zakāh is paid from each type according to its respective proportion. However, if this becomes difficult due to the large number of varieties and the small quantity of each individual type, then zakāh should be paid from a medium-quality variety among them — neither the best nor the worst — out of consideration for both sides [the giver and the poor recipient]. If one goes to the trouble of paying from each variety according to its proportion, this is also permissible." And Allah, the Exalted, knows best.