I actually use Sandfire Dragon Ranch's Treefrog dust on all my frogs (except clawed frogs). It really has brought out the color in my frogs, especially Kole, my male cobalt. It has an increase in protein, spirulina, and other stuff to bring out the color. I use it everyday almost for feeding. In a way, its kinda like Dendrocare, but has less Vitamin A, I think.
My tinctorius has had it since he was 8 weeks, and that was 9 months ago. He's probably 1.5 inches now, and very fat. All my mantellas were youngsters when I got them, and they are plump. One is now gravid. My three tricolors have nearly tripled their size, and are getting red. It works successfully on my firebellied toads too.