H2O change

I have done my first water change. I did it tonight at about 8:30. I changed out roughly 7 gallons. the tank is 38 so i figure i did a 20% change. The guys at fish doctors were EXTREMELY helpful with this. (http://www.fishdoctors.com/) I bought my R/O H2O there today. I'll have to update you Mon. as to how it went.