I have two elegance corals (so its n=2 ), one for about three years and the second for two years. IME, they do not seem to care about phosphate ( in my tank, it can reach 0.6 ppm) or nitrate (that hovers between 5 and 0) concentrations, and even when my KH dropped due to a mistake from my 8-9 target values to 6.5 for a few days, there was no apparent effect. I heavily dose carbon (x2.5 from the recommended limit) and amino acids (corals can take AAs from the water column directly) to feed the corals directly and supply a nitrogen source. My carbon is TM Elimi NP and TM Reef Actif once a weekElegance corals hate high phosphate, once I hit 0.15-0.20 my Australian elegance starts to show this is “unacceptable” behavior. I mostly have leathers and euphyllia so I run around 0.10-0.15. Australian are indeed tougher than the Indonesian.