As Loraxchick has said, I find that my bettas love any plant that they get to use. My own gets to use Cryptocorynes, elodea, java moss, Vallisneria americanus, Anubias nana and even java moss. Since it is merely a resting place for an exhausted fish, they will use whatever is handy at the time. I find that over time my Betta splendens use the refuge of plants less and less often as they get into better physical shape by actually exercising in the higher flow areas of the tank. Unlike many people, I do not consider my bettas as substandard swimmers and they respond to my lack of babying them by becoming stronger swimmers.