Last year, on my first attempt growing, I had two seedlings. One was doing great, and had new nodes practically every day, but the other was stunted. It wouldn't finish making it's second set of real leaves, and stayed that way for two weeks, otherwise appearing green and healthy. I didn't have any sort of patience back then, so as an experiment, I planted it in my aquarium, along with the other water plants that were growing/thriving. It actually stretched considerably, for about a week, before it "disolved".