I have never seen them for sale before, and only once in a pond. I have seen small Golden Trout for sale, but they are quite unusual too.

They are probably not popular because they need cool water and a lot of oxygen, so a garden pond in summer is going to need a lot of work to be suitable for them. They would also eat small fish.

Trout are very fast-moving and impressive fish if you have the time and space to keep them.

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Lucia