Other people are dismissing this idea right off the cuff because of the arsenic concentration but that's a good thing. Now we use it as a feed stock for arsenic loving single celled creature. Then we concentrate it further. And again and again until you have arsenic pure enough for use. Then you can add that arsenic back into the pesticide and herbicide production processes that helped it get into the seawater instead of mining it on land.
That's my thoughts here.
We have these LLM tools, and the questions is "We have X amounts of sargasso algae, and it bioaccumulates arsenic. What bioremedative pathways to accumulate and extract arsenic, in order to heal the oceans, make safer food, and get pure arsenic for the silicon GaAs Industry?"
I've a friend who has access to base 3d printers, and can print up to 12k RNA base pairs. We're now at the point of growing our own remediation.
The LLMs are sold as a panacea. Time to start having them carry their salt, or their gallium arsenide and silicon.