Proper nutrition and vitamin supplementation prior to breeding is important. Our frogs are supplemented twice a month with additional Vitamin A in the form of retinol, which is a usable form. There is much evidence that frogs do not have the ability to convert beta carotene into a usable form of vitamin A. Offering a fatty food, such as termites, flour beetle larvae or fruit fly larvae seems to produce larger and more frequent egg deposits.
I have good success with separating the pair from one another for a few weeks and then reintroducing the male to the females tank. Better yet is introducing a different male to the pair or playing a call of another male will also stimulate activity.
D tinctorius are best to maintain in pairs or a 2.1 group, meaning two males and one female. D auratus, P terribilis, D leucomelas, A galactonotus, Ameerega and others do fine in small groups.
Dart frogs do not perform amplexus when mating. In fact aggression and wrestling between same sexes might be misinterpreted as amplexus. Typically only males call and the female will show her interest by stroking or petting the males back. Less often a female will embrace the male frog. After some courting, the male frog will lead the female to a suitable place to deposit eggs. For larger frogs this will usually be a protected dark hollow with a smooth surface for laying eggs. We provide cocohuts or some other shelter over a petri dish or plastic lid.
It is not necessary to pull the eggs from the enclosure to hatch and rear yourself. Actually, you will miss one of the most satisfying parts of the hobby, which is seeing the male frog transport his tadpoles after they hatch to a source of water.