[mikeg8]

This article from Australia claims a 95% methane reduction using a native seaweed additive.

https://www.dcceew.gov.au/climate-change/publications/from-b...

[roboticmind]

That's still red seaweed ("FutureFeed’s solution uses a specific type of red seaweed"). It like other seaweed additive, can only really be used in feedlots where as mentioned above, only account for ~11% of emissions