I need to get a lightbulb for my live plants, help?

Petsmart and sometimes even walmart have "plant bulbs" for 5 gallons. If you don't want to buy any specialty lighting then this is about the best you can get. It will be fine for the moss ball and nana and should work for the others if your current light is. The duckweed is probably not the best for your 5 gallon it'll multiply too quickly and prevent the rest of the plants from getting sufficient light. It is normal for wisteria to grow roots while floating. If you let it float you'll have the same problem with it shading the rest of the plants as you will with the duckweed but if you plant it it may die so you'll have to work out a balance there. After the other plants get going you may want to remove it.