Please feel free to submit any idea, no matter how far-fetched or whimsical. This market is sort of a Hail Mary pass, a hope that brainstorming ideas might possibly connect the right idea with the right person.
Market as a whole won't resolve until at least EOY, but individual ideas will be resolved as "YES" after a time, once I notice they exceed 90% consensus and it seems enough traders enter the market. Ideas that have stayed below 50% will be resolved N/A (if Manifold will allow this) EOY.
My layman amateur take is that solutions involving small living organisms (bacteria, fungi, moss etc) are the way to go because there's way too much water in the ocean to ever practically put through a human-buildable quantity of mechanical devices (filters, electrostatics, hydrophillics etc) but the small organisms can exponentially multiply in a reasonable timeframe to the insanely vast quantities needed