Lemna minor is a hardy, surface floating plant that rapidly multiplies - suitable for both aquariums & ponds. By absorbing excess nutrients such as nitrates & phosphates duckweed acts as natural filtration & is very effective at controlling algae. It provides shade from the sun & creates a great nursery for fry Nutritious & natural food for healthier fish, turtles & waterfowl Auction is for 50g (large amount) I only ship on Mon & Tues to reduce risk of delays