FBTs that are captive bred are not as bright in color as those from the wild. It is recommended when purchasing this species that you choose individuals that are the most bright and colorful. Often frogs will turn a dingy green or even brown. Some captive-bred strains are becoming genetically weaker, with duller colors and smaller size.
To help retain some of the color, especially the bright red belly, feed your frog foods rich in carotene. Aphids are a good source of natural carotene for your frogs. You can try gut-loading your crickets, earthworms or bloodworms with shredded carrots, marigold flowers or paprika as well as the usual calcium and vitamin supplements. Also, you can add a small amount of canthaxanthin to the water. It is available from drug stores, veterinarians or chemical supply companies.
Unfortunately, loss of color is "normal" for captive-bred individuals.
