Well, I am no expert but a lot has been said about Stress and color. Stress can happen from diet, or having lived with a Salamander. From your comments I take it you are deducing that the death was caused by the Salamander due to some transferrence of parasites or stress and maybe not injuries? How long had you had the Toads before death occured? It maybe that if you had them for a short time, and then the salamander was introduced that they were already ill at the pet store and the salamander just made the stress level worse bringing on death sooner. There has been so much said about not mixing due to stress or parasitic transferrence, but let me tell you this as a person that agrees with not mixing-when I raised 700 FBTs from eggs as a kid and knew nothing, I had the parents and an anole, a Red Eye Tree Frog, some crabs, some fish altogether in one tank! I'd never in a million years do that now, but that is just an idea of how hardy they are when they are healthy. Just don't add anymore to the tank for 3 months-essentially quarrentine this guy. Keep giving vitamin covered or loaded food. And Paprika is supposed to help with the yellow/red colors. When you are ready, post again or write to me, I'll share excerpts from the journal I kept the summer I had 700 FBTs.