I'll leave the tank questions for the experts to answer, I'm a relative noob myself.
I can help you with your camera stuff, that I am an expert
Most cameras including DSLR will have crappy white balance straight out of camera (SOOC) with JPG. If you find/use a camera that can shoot RAW files, then you can use a photo processing software like Lightroom or Aperture to automatically adjust the WB, and it'll usually be pretty accurate to your "reality" colour. Some people use a white/grey card for indexing WB but I don't feel it's too necessary. With JPG you're always crippled in terms of post processing. You can try the WB settings in camera but I find those are usually pretty off.
Let me know if you have further questions.