I want to move our pond. I was really wanting to have a pre-formed pond because of the ease of it but I don't seem to be able to find a deep one. We currently have a wildlife pond which is what I want to keep. But it freezes to the bottom in winter (we're NW and experience -10C and more for days on end) and its about 50cm deep. So I wanted a deeper one but I can't find anything that is deeper. Do I have no choice but to dig and line a hole if I want it deeper? Or do the frogs and newts not mind it freezing to the bottom? We have frogs in the pond right now (its not frozen at the moment) so they obviously have survived the freezing somehow.
Also, I was wanting to get a waterfall / cascade feature as well. I assume that I just buy a pump and some tubing to do this. I assume then that I also don't need any sort of fountain because I've got the water being circulated through the cascade feature. Is this right?