I got these guys out of Dniester River, but they are all over Europe. They are completely freshwater. Yes, these river nerite snails actually breed in freshwater. Perfectly fine for any tank, cold water or tropical. They only downside is that they are much smaller and less colorful than marine and brackish nerties. This species is Theodoxus fluviatilis. Oh and these river nerites like to lay eggs on each other's shell. you can see it on these photos.