I have an odd pen cleaning method. Since I hate filling and emptying cups over and over, I do the first few flushes a little differently. With the faucet running, I make a cup with my palm to hold water, dip the nib in, and start flushing. I do this to get rid of the majority of ink. It has never been a problem before, as I keep the water running. I may get a faint stain on my hand, but it is never very noticeable. I never have a problem staining the sink. I tried this for the first time today with Baystate Blue. The results were much different. Let us say the wife was not impressed, especially since she just cleaned it yesterday.