Hopefully this will work this time. grrrrrrrr. If not I sent you a e-mail with this info in it yesterday.
There are a couple of problems with putting plants in a tank as you are getting. The main one is the lighting issue. 11watts isn't going to do crap as far as growing plants. At best it'll grow algae for a couple of feet or so. If you want plants your going to have to get some expensive lights to make them grow. OR your going to have to figure out a way to grow the plants with in the top 2 feet of the tank (closest to the light). If the lights on the tank are incandesent instead of florescent don't even bother with plants. They don't grow real well under incandesnent lights.
If you have your heart set on growing plants you can try Java Fern, Java Moss or any of the Apponogetion species. Those are all low light tollerent. I'm not even sure how well these plants will do with that little light.
I hope this helps a bit. Wish I could help you more with this but there's not much that can be done with the set up your getting with out getting better lights. Rose