Has anyone had some of your boats lines grow what appears to be green moss? If so have you figured out how to remve it? I have tried some household cleaners with limited success.
“Practical Sailor” magazine June 2011 did an article on rope care. Consensus was to periodically put them in a mesh bag and wash them with Woolite in a commercial washing machine.
Some sources say add a “little” fabric softener.
These recommendations may be a bit timid for your “green New England slime”.
Actually I have run all the halyards thru the washmachine in the past to cleanout the salt and make them softer again and it works. I think the green needs a stronger treatment. New England ingenuity will provide a solution I am sure.