Edit 4/3/13: The key to getting the background like this is to lightly spritz. If you spritz heavily the colors run together more, which is also very pretty, but different. I made a card last Summer with the colors more blended, but apparently I never posted it (since a search on Lovely as a Tree doesn't show it). I'll photograph it and post it so you can see the difference. We also found out at my class that it helps to have well inked ink pads (which is why you should always get the re-inker when you buy an ink pad).
After drying the card stock with my heat tool, I stamped and embossed the plant. The fish was stamped with River Rock ink, cut out, and added to the card with Stampin' Dimensionals. I added three rhinestones for bubbles and then put the card layers together -- card base of Whisper White, River Rock, Not Quite Navy, and then the stamped piece.