I agree that firebellies are too agressive to keep with newts...but I've heard of people doing it. As long as the tank was large enough and feeding was done is seperate places it may work...feed the newts underwater food all the time and the toads crickets in a feeding dish on land. The toads would have to be well fed and the newts would probably wind up rarely coming out of the water. I think these species share the same environments in Asia where they are found so it's not that crazy of an idea. Here are my suggestions for the best tank mates...zebra danios (regular, gold, blue, glo, etc) and an apple snail. This will make for an interesting tank. Once in a while toss in some ghost shrimp. The newts will eat any shrimp they manage to corner and any fish that happen to die off. Danios are quick and are more concerned with harrassing each other than they are anything else (besides eating). The snails are huge and interesting...just rememeber that they will eat EVERYTHING. This means any live underwater plants will not survive and any attempts at breeding will fail because they will eat the eggs. Gold Apples are especially eerie looking and hardy. Apple snails come from the Amazon and have spread to infest rice paddies all over Asia. They are considered pests there because they eat rice sprouts to the ground.