I am by no means an expert on this subject, but from what I have gathered they need a high protein diet including Astaxanthin & Beta Carotene (and other naturally occurring color enhancers). I've just recently started raising some Anthonyi tads myself and am feeding them Omega One Super Color Flakes, HBH Frog & Tadpole Bites, New Life Spectrum Small Fish Formula, frozen Plankton & frozen Cyclops.
I am keeping 6 tads in about 2 gallons of semi-shallow (2-3" deep) water that I steeped Indian Almond leaf in (provides nutrients and tannins). After steeping the almond leaf, I dropped half of it in the bottom of the container with the tads, and the other half I put in a gallon of water that I use daily to change a small amount of water in the tad's container (I just skim the surface of their container and top it off with the leaf water). There's also a layer of other small leaves in the bottom of the tad's container, as well as a few plant cuttings floating.
This has worked for me so far...I had my first pollywog walk on land today!
Best of luck!