From my own limited experience, my cynops tends to hide, but my taricha don't do much of the sort. Do you have very large ones in with very small ones? I would definitely recommend hiding spots in this situation. I only have two living together, and they normally hang out on the same plants together. I don't think they'd do much hiding even if they had a better spot. What's your setup like right now? How many newts do you have? What size tank?