Here's what I have noticed. I love those bottles and just used them with the paint. But before every use, I put them in the dishwasher on the sanitize setting with added heat. No soap, just the sanitize setting. Then one time I put a few in the starsan before filling. Something happened that took me away from the bottling but I left the bottles in the starsan. A few days later I got to bottle and when I took the bottle out of the starsan I noticed that the paint was rubbing off on my fingers. I took the bottles to the sink and used a green scotchbrite pad on them and all the paint came off. So I ma not sure how long you need to leave it in the starsan, and I don't know if you have to put it through an aggressive dishwasher cycle first. But now all my Stone IPA bottles are paint free.