Ovipositing amphibians select breeding sites that determine their offspring's larval habitat. Preference–performance theory predicts that adults will select habitat patches that match the expected performance of their offspring in those patches. Many amphibians breed in temporary ponds immediately after they fill, and one species, Hyla chrysoscelis (Cope's Gray Treefrogs), selects between breeding sites based on patch age differences of as little as 7 d. Prior work established that H. chrysoscelis have better larval performance in more recently filled ponds, but not in ponds less than 15 d after filling or among ponds that differed in age by less than 65 d. Our objective was to determine experimentally whether larval H. chrysoscelis performance varies across short time scales after filling (3- and 23-d-old ponds) and across two larval densities (15 and 30 larvae per mesocosm). Higher larval densities reduced metamorph mass and body condition, but did not otherwise affect larval performance. There were lower survival, shorter larval periods, and slightly lower mass and body condition among larvae from 3-d-old ponds than those in 23-d-old ponds. These mixed performance differences across our two levels of habitat age might not necessarily be representative of what happens in natural systems, however, where older ponds have more established communities of competitors and predators.