Just a heads up, I will be on vacation until next Tuesday. So that last post will have to tide you over until early next week.
Enjoy your vacation!
I guess this gives us a good 5~6 days to discuss the merits, ins and outs of Mediaeval aquaculture (;P) j/k I'm sure other things will come up as well.
It appears that fish farming was mostly a thing for the pious who weren't allowed to always eat meat, and since not all monasteries were close to rivers or had ready access to trade for fish. they would indulge in aquaculture (fish farming) for their protein needs.
I know that at least in Japan and Hawaii farmers would keep fish in their rice and taro paddies. (catching shiny carp mutations and selective breeding in Japan led to Koi-Carp) fish in Paddies actually help with fertilisation and I would imagine pest control as well.
In the stronghold games you had eel/lampray ponds to be made into honour goods (food for the nobility) I guess this was a thing as well?
The Hippy in me mostly likes fish farming because it doesn't drain natural fishstock from the river, In mediaeval times overfishing probably wasn't as much an issue as it is nowadays. but I still see moving away from exploiting natural resources without putting effort into maintaining/replacing them as general good stewardship. (when I was in Stockholm for holiday I saw that they actually breed and release a lot of salmon into their river and I saw a lot of people fishing in the city)
Modern fishfarming (aquaculture) gives a lot of pollution because they often raise carnivorous fish as luxury foods and dump the waste instead of using the waste. Aquaponics is an interesting field, which combines aquaculture (fish breeding) with agriculture (plant growing) (on youtube you can find plenty of backyard smallscale farmers)
Us being on a river makes fish-farming really not that important though, the monks in ye olden times did it when they had no access to the rivers (I believe there are also forms of fish breeding that don't go into manmade ponds, but instead use fish that are kept in secured nets with floaters in natural bodies of water)
and seeing as our culture doesn't employ flooded paddies in agriculture the fertilisation argument doesn't really hold either.
still, I think its a 'cool thing to do' ;P