Christmas moss is one of the mosses that does better with some form of CO2. A good running yeast/sugar/water DIY should work just fine. Adding nutrients helps too.
http://www.aquascapingworld.com/plan...hp?item_id=114
I know what you mean about being broke. If I want something, I have to save up my pennies. It took me 5 years to get everything that I needed for my 40BR. LOL!