oysters fresh /salt water,story continued.?

Question

thanks everyone who replied, adverts on telly always say ask your fishmonger, so i did, i went to morrisons in kirkstall leeds.and asked them, as they where selling fresh scottish oysters, i asked are they from salt or freshwater, he didnt know, so he went to ask, came back with the reply fresh water, thanks i said i'll let you know in two weeks if they survive in my pond with running water, poor lad just looked at me daft,
[e-mail]

Answer 1

Oysters sold in fishmongers are salt water and would not survive in your pond.
They are grown in the sea in special beds and harvested especially for the fish trade.
For this type of pond the best shell fish are swan mussels which will live in a pond and feed by filtering the water.

Answer 2

Yep it is always good to ask, since there are more than 40 kinds both fresh and salt. there is no reason if your pond is freshwater, and you put them in the pond they won't survive. They also have what they call seed oysters. You can seed a section of your pond with them and they will reproduce quickly.