So you're saying that the term "chasing numbers" is just referring to nutrients in this thread? Well then, yes, I got off topic a bit...sorry.Harrr but you see the question is about acceptable range of (so called) vital water quality parameters really. That is more or less what this thread is about given so many have (so called) unacceptably high poor water quality parameters. yet have flourishing SPS reef tanks. Often the people chasing numbers are the ones who are experiencing some form of issue in their tank.
As far as the acceptable range for nutrients and sps, I think it is much higher than zero zero, for certain. My acros don't seem to like NO3 much higher than 5 ppm, but I have seen (on this website) really excellent sps tanks that claim to have much, much higher levels, so there appears to be other factors involved. I have no skimmer and seldom run carbon, so perhaps dissolved organics cause my acros to be less tolerant of higher nitrate. I have been wondering about this for some time (yellow water definitely impairs lighting effectiveness) and have already purchased a skimmer for my new tank.