On ok.. flame angel says should not be exposed to more than .15 ppm. I was thinking it said .15 mg/l so was thinking .50 mg/l was way too much. What is .15 ppm equivalent to when measuring mg/l?
my point was that your .15ppm is likely for copper. The .5ppm(or mg/l) is for the CHELATED COPPER. Chelated copper is not as toxic as copper so your fish should easily survive a .5ppm copper concentration if it is chelated copper.