I had a battle with it, of course it was my own doing most likely. I upgraded tank size and used new sand, and all new water for the set up but used the old rocks to be able to transfer everything to it and being one to try and stay on a schedule of maintenance.... kept the 2 week water change schedule and shortly after it started. Finally got rid of it by not doing water changes for 4 months, and now it is 99.9% gone. However unless the nitrate test kit is expired or something wrong with it, it is the Red Sea one, I think I will need to do a few more water changes like maybe 2 or 3 more within a couple weeks or get the Red Sea no pox because the test shows the nitrates in the 50+ range, however the test strip shows them to be under 20 and all the corals and fish look good, except for the 2 corals I had to replace because the fish killed them by constantly knocking them down and the green star polyps that appear to have been EATEN by my flame angel. Even my Acro is extending polyps every day so part of me wants to say there is something wrong with that nitrate test kit... but rather be safe than sorry, but do not want that red s**t coming back either.