2nd on most of these comments.... Java Moss is tough and all you'll need is a golf ball sized piece to have enough for life lol I've had my java moss repopulate a tank once only from one piece I neglected to remove during a "take out" of it. It's hard to get rid of for the most part, especially if it attaches to something. 6 bucks isn't too bad since it'll only need to be bought once and you can put in almost any tank.. not a very picky plant.. grows like a weed on steroids IME... (2 WPG, no CO2, no fertz) Couldn't imagine a high tech set up with that stuff lol