Well, everyone seems to do quite well with java fern under most conditions (except for me.) I think it is pretty hearty and the goldfish don't bother it, but mine never look as nice and lush as some people who grow it.
Is it like anacharis where you can cut it and grow it and everything? And what is taller? I need something for when I eventually convert it to a betta sorority
They can get pretty big and grow well. It isn't a stem plant like anacharis. Java fern spreads by rhiozome (hope I spelled that right). They aren't a food supply for fish like anacharis is, but they are very attractive-- especially the needle leaf and trident varieties.