Q. See question above. Does one have to feed the fish in his aquarium before he eats his own meal?
A. Sheilas Ya’avetz (1:17) addresses the prior question regarding eating one’s meal before feeding his cat or dog. He debates that this household pets may be different to the cattle animals mentioned in the Shema, since they don’t have when corraled access to grass or food. Dogs and cats at home may be different, depending on the case.
Mishne Halochos (6: 216) following the above reasoning maintains that aquarium fish may be similar to cattle, since they are also limited to their secluded environment.
However, Shevet Hakehosi (2: 149) maintains that fish in an aquarium may survive if there is plants available or food left over that does not discompose.
Rabbi A. Bartfeld as revised by Horav Dovid Pam, Horav Aharon Miller and Horav Chanoch Ehrentreu Shlit’a.