I'm definately no expert on fish, but you mentioned an albino dwarf frog. I wouldn't put this in anything smaller than 20 gallons as they grow very quickly and get very large. Trust me. I was sold one for my son 2 years ago labeled a albino dwarf african clawed frog. Anyway, he's now about 8" from head to bottom, not including his legs when he stretches out. And he eats absolutely everything in site, so not sure I would put smaller fish, your newt or even your other frog in with him. My son keeps a couple red eared slider turtles with his frog if this helps and has a 25 gallon aquarium.