Dishwasher smells are typically produced by the accumulation of trapped food particles or oil. They can block the filters, spray arm, drain hose and other nooks and crannies of your dishwasher. If these food particles are allowed to accumulate over time, they begin to smell and emit fishy or foul aromas, which can then migrate to your dishes. Germs then can begin to grow in your dishwasher, making it a breeding ground for bacteria and mildew. To avoid the problem, do a monthly maintenance cleaning of all components.