I never said "we can't learn anything from anecdotal observations...". Anecdotal observations are often the beginning of understanding. I'm just pointing out that on this particular subject, we don't have near enough information. So, when you said you had gone over 1,000's of ICP tests and corisponding images, I was kinda excited to see it. It seems like you're on top of your own data and information. Props for the details and observations. I read them and think you're doing a bang on job (though I really like a spreadsheet of all your parameters on this journey you're on so we can maybe see a trend).I agree, to say that we can’t learn anything from anecdotal observations is a little fierce. Yes, there are a lot of variables at play, and the chemistry is always changing, but when you keep data with several tanks over several years you start to see better results with certain ratios and nutrient levels. This is not exactly the same for every system, and does also depend on the age of the system, but from what I’ve observed in my own tanks is that higher PO4 level and N-P ratio just does better for me personally. This is coming from somebody that tried to run at the low end for years, and it always seemed that something was off. I’ve had much clearer water, less algae, cleaner rocks, and better coral growth at 100:1 then I’ve had at 14:1. Higher nutrients in general just seem to be better for Acro’s. I honestly don’t think many people realize just how low .03 ppm actually is. I’ve even seen well established systems at .02-.03 ppm, and the corals are just pale. Maybe they didn’t have enough nutrients/nutrition going in. Maybe their overall chemistry was lacking. IDK. Just because a coral can tolerate .02-.03 ppm doesn’t mean they like it. Our tanks really don’t have enough food available. What we do provide typically fuels undesirables more than it feeds the corals IMO. For that reason alone I’d almost rather dose organic carbon to give the corals a food source, but also strengthen the bacteria population. Elements that boost algae (Fe, Mn, NO3, PO4) also benefit coral health which is why I typically dose them all depending on demand even though it may seem counterintuitive to some.