https://grist.org/science/researchers-explore-mining-seawater-for-critical-metals/
The aim is to draw key minerals, including lithium and magnesium, from ocean water, desalination plant residue, and industrial waste brine.
And in 10 years: Fishes are dying due to the severe lack of nutrition in sea water after humans exploited it for mining of metals. We're not learning of past mistakes.
lol and what else
this process is already in use in dead sea chemical works and it's about separating magnesium, just this time it uses desalination brine as an input
so it gives some table salt, and depending on what you want it to output, potassium chloride, magnesium salts or metal, gypsum, lithium
Returned brine is damaging to seafloor so returning less salt is a net improvement
Don't worry we already ate most of the fish. The remaining fish don't need all the minerals they once did.