I have one open-topped small stock tank in my basement, 5-foot diameter. It's not heated and sits up on conrete blocks a couple feet off the floor, so it's usually a degree or two below ambient air temperature, which can be as high as 75F in mid-summer and as low as 58-60F in mid-winter. I use a dehumidifier sized appropriately for the volume of the basement and attached crawlspace. It seems to be quite capable of maintaining the humidity between 40 and 50% in the summer, when it runs almost continuously. In the winter, the humidity stays around 40% on its own and the dehumidifier rarely turns on.
The basement is heated entirely by electric heat; the wood-burning stove upstairs doesn't really do anything for it. The dehumidifier generates a fair bit of heat when it's running...meaning that it's helping to heat the basement in the summer when I don't need it...and not heating at all during the winter when I could really use it...