So... hey all! Still mostly just a lurker (except for that fly-by-night post ages ago... sorry!... I think I think y'all are intimidating with your mountains of knowledge lol!). Any-who, I felt compelled to share this for the rest of the lurkers who may have doubts about BKF. I've, of course, heard about it, but never seemed to run into it so I just kept on with my same old, same old routine. Soaking, or Dawn, or white vinegar, or Efferedent, or brushing, or what I like to call the "shake, rattle, and roll" - or various combinations thereof. Finally... my local shop starting carrying BKF powder so I snatched it up. Um... yea... AMAZING! This sad little bottle has been on my shelf for years, and was subjected to all my tricks. As you can see in the before, didn't work so much. The after photo was, literally, 15 short minutes of me just lazily rattling around some fish tank gravel, some BKF, and a bit of water while binge-ing on Netflix. (I hope the difference comes through in the pictures well - I lost the natural light. There's a storm brewin' here in the 603.) TL;DR - It's amazing. Buy it. Use it. Love it!