Seaweed is great - it also pulls excess nitrogen out of the water, can be co-cropped with bivalves, can be fed to cows for decreased methane production, can be eaten directly in many forms…

If we had an actual price on carbon seaweed production would be a boom industry.

Couldn't you use it in large tanks to suck out CO² directly from the air? What makes this more expensive than currently proposed alternatives? Even if you don't use the seaweed in the end, you could just dry and bury it I guess?

EDIT: After some research I found an interesting article addressing this: https://www.technologyreview.com/2021/09/19/1035889/kelp-car...

That is an interesting link, thanks.