your GH/KH is very, very low.
You can using epsom salts to increase the GH, and baking soda to increase the KH, but this raises the total disolved salts int he water and you ewill need to do this slow and whatever you do, keep it consistant.
The water that you do water changes with, if you can find water that is harder then you will do better in my experience.
Also make sure that you use start right, or some thype of water stabalizer when you are doing your water changes unless your 100% positive that your water has no hard minerals etc, and even then it cant hurt to use a water stablaizer.
my water that comes out of our water softener has a KH and GH lower than yours, and i had a very rough time getting my aquarium running correctly until I water changes with nothing but the pure well water that has a KH of about 120ppm, then after about a month everything started falling together and working and now I have a very happy, healthy aquarium.
With a KH and a GH of where you are, adding co2 eventually will be difficult.