Please, what is the stance of the Sharia on feeding fish with the flesh of dead animals like poultry, goats and cow?
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Scholars held different views regarding this matter. The view which we hold as preponderant is the chosen view of the Hanbalis, namely, that it is permissible to feed edible animals impurities if they will not be slaughtered or eaten soon. If the animal is to be slaughtered or eaten soon, however, it is prohibited to feed it on impurities.
Kashshaaf Al-Qinaa‘ reads, "It is permissible to feed the animal on impurities if it will not be slaughtered or milked soon ... because it is permissible to let the animal graze freely and it is known that it might eat impurities..."
Al-Mubdi‘ reads, "It is prohibited to feed the animals on impurities if they will be eaten or milked soon, but if the slaughtering or milking is delayed; it is said for the considerable period of time in which it is kept away from eating such impurities before slaughtering them, then the most likely correct view is that it is lawful to feed them on impurities, just like the case with the inedible animals according to the preponderant scholarly view."
Hence, there is no religious impediment to using the meat of dead animals to feed these fish provided that you stop feeding them such food before selling them for a period of time that is sufficient to make their flesh pure and allows the traces of impurities to disappear. If the Jallaalah (the domesticated animal fed on impurities) is kept away from the impurities until their traces are removed from its body, then it becomes lawful for consumption according to the consensus of scholars.
Allah knows best.
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