I keep males up to 800/900 grams in 15 quarts tubs to ensure that they eat while breeding. Few years back I have noticed that smaller males 500/700 grams (not all but enough of them) would often go off feed during the winter/breeding season, no big deal for those not being paired, a little more of a deal for those that were, so like any animal that would stop eating for a certain period of time I started to downsize a bit and sure enough they resumed feeding (nothing new there). From that point on I decided that every winter/breeding season rather than fix an issue I would prevent it, so all males under 800/900 grams get moved to 15 quarts.
It's been working very well they eat and breed which is exactly how I like it, having male that stop eating and are being paired can take it's toll very fast compare to having a pet that stop eating so to me it was essential to make sure that it did not happen to start with, of course it's not the only thing making sure that males are not overfed throughout the year will help as well.
Larger males are in regular 32 quarts tubs and really do not care they eat no matter what.
The psychology is easy and has been proven downsizing offer added security and will in most cases alone help an animal resume feeding of course if it is an animal that hit "the wall" it a whole other ball game.