Yep, the parrot/canary supplement is usually canthoxanthin. It works but you have to be careful.
Ben Green recently posted pics of vittatus that showed one that was fed beta carotene fish flake food as a tadpole and another that was not. My experience with this same line has been that if you don't feed the color enhancing flake food, then you will never get the bright red-orange stripes no matter how much you supplement with paprika after they morph. Like Corey, I think the tadpole stage is really the key point to get the color on frogs. That's a little hard to do with pumilio.
As far as whether the bright pums keep raised in the viv keep their colors into adulthood, the jury is still out but it looks like they might. The first froglet I tried this with matured into a bright red female who was beautiful. I put her into a newly planted 20T with an F1 male and the next day I found her as a crispy critter on the floor. The top to the viv had gotten pushed back enough to leave an opening. So I didn't get a chance to see how long the colors last. The second one to come out of the large viv was also really bright and I put it into a rearing viv with some siblings. A few hours later I saw a male harassing it so I put it back in the large viv. I saw it for the next couple days looking normal but now I haven't seen it for a couple months. I don't know if it died from the ordeal or maybe it is still in that jungle and now indistinguishable from the adults. I have a third froglet that is approaching adult size and I got a good look at it yesterday. It looks marvelous. Hopefully it will stay that way.
Corey, did I send you that pub on rhodopsin and frog pigment? I'm not sure what to make of it and wondered if you had any thoughts.