In salamanders, three pairs of external gills provide for oxygen in take. Amphibian embryos generally remove waste in the form of ammonia. The majority of amphibian larvae are aquatic. Unlike the embryos, amphibian larvae obtain nutrients from the environment for development and growth. Most larvae feed on small aquatic invertebrates.
Some amphibians eat algae and continue to feed and grow until there is no more algae left.
Larvae growth rates are dependent mostly on temperature and food availability. Some chemicals left by previous larvae can slow growth down. Anurans tadpoles are mostly short and develop length through growth, in salamanders the larvae are long. Most species of salamander and anurans stay in schools as larvae. They stay in schools to avoid predators and to have bigger food supply.