There seems to be no known source for feeding the fish at Tashlich. As already noted, those who mention it then to be opposed to it.
But the fact is that it is mentioned - and its origins seem to be almost as old as the Minhag of Tashlich.
Regarding feeding the fish at Tashlich we could learn from the Aruch HaShulchan's opinion regarding feeding the birds ...
The Aruch haShulchan 583:4 says that woman should not go where the men go for Tashlich. http://hebrewbooks.org/pdfpager.aspx?req=9102&st=&pgnum=284
I would imagine that the reason is in order to avoid mingling.
In the seffer haminhagim of the Maharil, the source of tashlich quoted in the Ramma end of siman 583, he mentions in hilchos Rosh Hashana ois 9 when going to tashlich on Rosh Hashana to be carefull not to take food along so as not to feed the fish, which people would do for fun while they were there.
It has been proposed that this seemingly innocent act of ...
According to this article it is "ideal" to use a flowing, natural body of water that contains fish and is located outside the city boundaries (MA 583:5; Kitzur Shulchan Aruch 129:21).
I am guessing that nothing except they both have a kabolistic prayer after them
We can probably understand this better by seeing the prayer said after both procedures
Starts with May it be Your will.
What I see is that chometz removel (a biblical mitzva) is connected with the removel of evil power (Egypt) that ruled over us by ...
I was in Yerushalayim for Rosh Hashanah this year for the first time. I saw in Yeshivas Netzach Yisrael in Rechavia that they had a small fishbowl with two goldfish swimming in it to be used for saying tashlich. This would seem to imply that they hold there is no minimum size requirement, and it need not be a "natural" body of water, but that the presence of ...