Hi Travis,
Atelopus are problematic for a number of reasons. The first is that the majority of species are montane and need cool temps. The second is that other than spumarius, none of the species are not exported legally (and most are critically endangered due to chytrid infections, habitat loss and over collection for the pet trade, I think somewhere of the 80 or so species of Atelopus 15 are already extinct). Most of the Atelopus species that do show up (legal and illegal) are in very poor condition as they do not take well to improper handling and are usually heavily parasitized. Many have multiple sores and septicemias/fungal infections. There was a confiscation of around 400 dart frogs and atelopus several years back (including A. zeteki) of which despite immediate medical care none survived more than a few days (despite husbandry infor provided by the Baltimore Zoo on the care of Zeteki).
At least with Zeteki, stress seems to readily bring out latent chytrid infections rapidly killing populations of the toad. (One of the Zoos built a huge display for Zeteki, stocked with Zeteki, had them living in the cage for months and doing fine, put it on exhibit and the Atelopus all died within weeks from chytrid.)
Baltimore and several other Zoos have bred Zeteki multiple times however the tads are very difficult to rear without the proper foods (they feed on brown diatoms).
Any other questions?
Ed