Hi Alex. I disagree with everyone (as usual lol).
You can use a supplement commercially called Naturose (scientific name is Astaxanthin) which is a dried red algae from around Hawaii.
You can also use dried Marigold (Zeaxanthin and Lutein).
These are high in antioxidants, actually some of the most powerful ones known. They are also color enhancers.
Allen Repashy has a commercial mix of these that are all combined called
SuperPig. The Naturose affects reds, and the Marigold affects Yellows.
So over time, you will notice a difference in the intensity of the color. This is a trick the reptile community has adopted from fish keeping, and is relatively unknown still, I think it will become as common as using calcium in several years.
The antioxidant value alone is a great reason to use this dust every day or every other day. I use it with every dusting and I notice that it works really well with my frogs and geckos, but my chams haven't been on it long enough yet to see a difference.
It is a pigment enhancer, so it takes time. If you are consistent, it will improve the colors.
One thing to keep in mind, is that starting the animal on this at a young age (from hatching) has the absolute best results.
edit: paprika also affects yellows, but the SuperPig will be more noticeable. If you DO get paprika, make sure it isn't the hot kind!
edit: Found this as an example for you. This post is frogs supplemented with the color enhancers I mentioned, and go a few posts down by the same user, and you'll see the colors of the frogs 'normally' in captivity:
http://www.dendroboard.com/forum/general-discussion/26836-color-enhancers-2.html#post243541
The dart froggers were the first in the herp community to start using color enhancers, so they have the most advice about it if you want to look around that website for more info.