Dishwasher slow to drain, have to clean every few months.
Sorry, I'm at work right now and don't know the make/model of my home dishwasher. I DO know that it's on the old side, at least 12 years old, but it still works perfectly (other than this issue) and doesn't leak.
About two years ago I noticed that the my dishes weren't as clean as they normally would be. I checked the bottom of the dishwasher and found it to be dirty. I cleaned it and my dishes were clean again and I thought nothing of it. Several months later it happened again. I cleaned it again, this time making a mental note of the date. About 4-5 months later it happened again, but this time I noticed it slowly accumulating in the bottom of the dishwasher. It seems to get exponentially worse; it takes several weeks to get a little bit on the bottom, but then it takes less time for it to get worse, and even less time to get worse still.
I had an appliance repair guy in to take a look at it. He doesn't know what the problem is; the dishwasher is level, the drain is clear, and all of the pumps are up to spec.
What's causing this and short of replacing the dishwasher how can I fix it?
Is this a good question?