Was having a lot of trouble with white balance in #Darktable, but this post and this post helped a lot. #photography

The way to deal with colour balances that are far from daylight is to use the "custom" settings where you have a hue and chroma sliders. It's often easiest to use the colour picker on something you want neutral (it defaults to the whole image - the edges, which usually works for me), or one of the auto modes to choose an initial starting point and then adjust from there.

And just to expand on bloodyTribology's excellent answer, when adjusting the hue and chroma, you are trying to match the colour of the illuminant (light source), not the colour/tint you want for your image. So, if you took a shot in a room with a tungsten bulb, which is a very warm yellow, you could use the custom setting to set the hue and chroma sliders to match the warm yellow cast of the bulb, which would then make the image more blue. It might seem a little counter-intuitive if you're used to warming up an image by moving the temperature slider to a warmer shade, for example.