China has the world’s largest distant-water fishing fleet, and Chinese vessels fish far beyond China's coastal waters like in South America, West Africa, Indian Ocean.

That's an interesting fact but that does not tell me anything about the possibility it has of raising salmon in its own waters

Why would they need to do it in their own waters?

Because fish farms are generally stationary?

Is it not possible to build a floating farm in international waters?

The point is that a pen far away from the land might not be very practical/much more expensive to take care of

Seems like something that could be negotiated with other nations in a peaceful way, if fishing was the only concern. The sub fleet is the real concern though.

I don't know, but being stationary in deep water isn't trivial task. You can't just drop an anchor when you have 3000-4000m of depth below your feet.

They are doing both landlocked and mobile deep-sea methods farming with success. In typical Chinese fashion as they have done with Fruit and other food productions, I wouldn't be surprised if they could scale it 10x within 5 years. I doubt it will take away Norway's supply to Japan in the short term due to quality and trust issues. But export to China may be lowered.

You can farm fish outside territorial and exclusive economic zone waters. But in any event China has substantial EEZ waters: https://www.marineregions.org/gazetteer.php?p=details&id=848... Taiwan isn't much of a hindrance. For one thing, the Strait is 100 miles wide. And China's coast is much, much longer than Taiwan.

Check your map: with the exception a part of South China Sea that is a point of contention with Vietnam, China only has access to shallow water (For instance East China Sea is ~300m deep, which isn't significantly deeper than Norvay's Fjords).

On the contrary the eastern coast of Taiwan has access to very deep sea though.

(This is a well known geostrategic fact, as the small depths of Chinese water are a big weakness for their submarine fleet).

I assumed concentration is a bigger issue than just depth? If it’s done in open sea instead of fjords that also should be an improvement. Of course fish farming in entirely unprotected open sea waters might be trickier