Stopped GFO about 6 days ago and today i messure 0.2 ppm no3 (was stable at 2.5 ppm for quite a while) and 0.03 po4 (was reading 0 for quite a while). Lets hope this has balanced out and that the tissue loss will stop. Im betting my money on phosphate limitation and overuse of GFO as a leading cause for the STN