Neuro-algae comes from the planet Appoce, Its gathered from the underwater volcanos deep below the planets green ocean. It's main side-effect is tentacle growth, which is considered a benefit by the Octopods.
Mkkt Bkkt once brought neuro-algae to the crew of the Yrdal Gedal station and made everyone high and grow tentacles on their faces, which in turn caused some panic within the Mido Confederation, as they believed it was a Nivelian attack.