Look in the iPhone App Store. I use a couple apps to kill the overly blue look and make them more realistic. The two I use are free. One is called "Aviary" and the other is called "camera+". Hope that helps. These will each allow you to adjust the white balance (or "color temperature" as they call it), and saturation to where it looks more realistic
Amazing pics by the way, your tank is one of my favorites on here