I have an unstained, acid washed, polyurethaned concrete floor in my home. Over the past few years I have noticed that in high-traffic areas we are getting some kind of build up in lace-type patterns. They almost look like water spots on a car when it isn't dryed well after a wash. My wife and I are considering the purchase of a Hoover hard floor steam cleaner to keep up the floors. We attempted a little "cleaning" in the kitchen and partially stripped the floor in a few spots due to our "enthusiasm". Has anyone here seen spots like the ones I've mentioned or do you have you have any suggestions for cleaning, or fixing, these areas? I also got a quote from a local company that does work like my floor and he suggested a complete strip and reseal. The price seemed a bit high and wanted to see if you guys had any ideas. We used a water based poly. Thanks!