Little White and Little Black

We are pretty busy with our two little fish these days. They are Little White, a white molly and Little Black, a black molly. They are tropical fish. We are absolutely beginner on raising fish. Initially, I bought a betta as a birthday gift to Cathy just for fun. But now, we become more and more serious about fish.
Little White and Black got sick yesterday. We didn't know what to do. So Ling surfed the Internet and found some information. It's a disease called Ick. She gave them 3 hot water bath yesterday. It worked. They are getting better after that. We went to the store and bought Ick-guard. We are giving them treatments.
After consulting some fish experts in the store, we think that fish need more space to be happy. We plan to buy a bigger tank with a heater today. I'll post a picture of Little White and Little Black when they recover.
Here are a few useful fish links:
http://fish.mongabay.com/diseases.htm
http://badmanstropicalfish.com/meds/ick.html