Oh My Gawd Kelly ! Buck The Great ? Dont you know that drugs are illegal ? I dont know what you are smoking but that was tooo funny :lol:
As Wasserpest wrote you do also need to know your GH/KH to determine CO2 content.
If you dont want to buy that kit just bring a tap water sample to your LFS and ask them to test for them, normally they will do that for you. If you keep up on regular water changes you only need to really test for that once and it will keep you within your "known" ranges unless you have extreme water conditions that require buffering, then in that case , regular testing is necessary to be sure you have adjusted properly.