Sea Lettuce, Ulva lactuca, is a cultured product that is found in shallow waters up and down both the east and west coasts of Florida. It removes nitrates and phosphates and can be used to feed sea hares, tangs and some other invertabrates. We have found that it reproduces the best in high lighting and low flow areas. When you order our cultered sea lettuce, it is stuffed in a 4 inch bag that is at least 6 inches in length. We try to aquaculture it as much as possible.