Wildlife Spotting

Salamander larvae or wood frog tadpole? We found a very small egg mass (6 eggs) in a vernal pond in Ipswich, Massachusetts. We brought them home and are keeping them in a container, although we didn't think the eggs were viable. The gelatinous mass around them was floppy and cloudy, not firm and clear. But they all hatched within days. We think they are salamander larvae, but we're not sure. External gills very visible. Most of the time they are still, but when they swim, they swim rapidly in small circles and seem very different than tadpoles. Length is a bit longer than the diameter of a dime. We are keeping them well-supplied with fresh pondwater and will move them to a container where they can climb out onto land.