I feed sugar beet shreds (briefly soaked in boiling water) - usually still warm and not sloppy and for the wethers with a dusting of oats only (no other concentrates once they are older than 12 months). Only smallish quantities though, as I found wethers do tend to run to fat quite easily...
However I live in an area of really soft water - if your water is quite hard you maybe need to either add some specific additive to your feed (available for cattle - I think it is Ammonium chloride) or use cider vinegar in his drinking water. cider vinegar is good for quite a few reasons, ad you can get in relatively small containers in the feed merchants (in the horsey section).