Yes if you are in a country that constantly has 'tropical' type temperatures, if you are anywhere in the UK, Europe and a lot of places in US that have cold winters... then no.
Cooler temperatures rarely kill cold blooded species, it just slows down their metabolism (eg snakes go into brumation and other species go into hibernation) but they cant function like this for long.
Keep tropical fish or amphibians in cold water and they will survive as long as it takes for them to die because they cant physically digest their food properly or take any nutrients from it.
It really wont be difficult just to get a small heater for your tank if you really want them...
