I purchased an Aquascape pond planter which will be used indoors.

I did some research and of course all the plants I like are invasive. This is only 14" tall 32" in diam. There will be a small trickling fountain and also some filtration as I will probably be adding 2 small goldfish in the near future. As you can see there are some holes in the back of fountain for plants. I would like a backdrop and something floating. The room it is in gets filtered sun. (my terrariums do well in here) it is the ONLY room in my house with sunlight. I have not yet put a plant in a pot in this room. Help Please :)