About a fifth of the world’s annual wild fish catch, amounting to about 18m tonnes of wild fish a year, is used to make fishmeal and fish oil, of which about 70% goes to fish farms

https://www.theguardian.com/environment/2021/feb/11/global-salmon-farming-harming-marine-life-and-costing-billions-in-damage

Among other environment impacts too. All kinds of fish farms dumps lage amounts of waste into the environment

For a world annual shrimp production [in fish farms] of around 5 million tons, 5.5 million tons of organic matter, 360,000 tons of nitrogen, and 125,000 tons of phosphorous are annually discharged to the environment

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3353277/