Seaweed runs

Two seaweed patches lie underwater off Fossil Island. Plant a seaweed spore in each, and 40 minutes later pick the giant seaweed: at least three a patch, and more the higher your Farming level and the better the compost. Sell it, or use it in your own Superglass Make, where it makes more glass from the same sand than ordinary seaweed. Yields follow the game's own formula as the OSRS Wiki gives it.