Could you please register your fish as "forge:rawfish" so they can be compatible with Pam's Harvestcraft recipes?

I'm not gonna support any of Pam's Harvestcraft horrible tags, that does in no way follow naming stantards - as stated in https://github.com/TeamMetallurgy/Aquaculture/issues?q=is%3Aissue+is%3Aclosed
We have our fish in forge:raw_fishes, which is used by other mods. https://github.com/TeamMetallurgy/Aquaculture/blob/master/src/main/resources/data/forge/tags/items/raw_fishes.json

is there any way to change these tags manually?

Yes, you can always add new ones with a Resourcepack/Datapack, like you would with any vanilla stuff

if you use CraftTweaker

var add_tag = [<item:aquaculture:arapaima>, <item:aquaculture:atlantic_cod>, <item:aquaculture:atlantic_halibut>, <item:aquaculture:atlantic_herring>, <item:aquaculture:bayad>, <item:aquaculture:blackfish>, <item:aquaculture:bluegill>, <item:aquaculture:boulti>, <item:aquaculture:brown_shrooma>, <item:aquaculture:brown_trout>, <item:aquaculture:capitaine>, <item:aquaculture:carp>, <item:aquaculture:catfish>, <item:aquaculture:muskellunge>, <item:aquaculture:pacific_halibut>, <item:aquaculture:perch>, <item:aquaculture:pink_salmon>, <item:aquaculture:piranha>, <item:aquaculture:pollock>, <item:aquaculture:rainbow_trout>, <item:aquaculture:red_grouper>, <item:aquaculture:red_shrooma>, <item:aquaculture:smallmouth_bass>, <item:aquaculture:synodontis>, <item:aquaculture:tambaqui>, <item:aquaculture:tuna>];

for item in add_tag {
    <tag:items:forge:rawfish>.add(item);
}

if you use CraftTweaker

var add_tag = [<item:aquaculture:arapaima>, <item:aquaculture:atlantic_cod>, <item:aquaculture:atlantic_halibut>, <item:aquaculture:atlantic_herring>, <item:aquaculture:bayad>, <item:aquaculture:blackfish>, <item:aquaculture:bluegill>, <item:aquaculture:boulti>, <item:aquaculture:brown_shrooma>, <item:aquaculture:brown_trout>, <item:aquaculture:capitaine>, <item:aquaculture:carp>, <item:aquaculture:catfish>, <item:aquaculture:muskellunge>, <item:aquaculture:pacific_halibut>, <item:aquaculture:perch>, <item:aquaculture:pink_salmon>, <item:aquaculture:piranha>, <item:aquaculture:pollock>, <item:aquaculture:rainbow_trout>, <item:aquaculture:red_grouper>, <item:aquaculture:red_shrooma>, <item:aquaculture:smallmouth_bass>, <item:aquaculture:synodontis>, <item:aquaculture:tambaqui>, <item:aquaculture:tuna>];

for item in add_tag {
    <tag:items:forge:rawfish>.add(item);
}

Oh, that's exactly what I needed! Thanks a bunch~