Tropical or Freshwater plants

Question
What kinds of plants can we add to a 30 gallon freshwater tank with guppies, gold fish, betta fish or any kind of Tropical or freshwater fish?

Answer
goldfish tend to eat plants... so if they are for decoration then I would add the cheapest plants possible... and plan on replacing them often.  Either type of plant will be fine... Tropical in this case means warm water not salt water.  Anachoris is a good choice.... dave