high alk and low calc

Hi everyone, I’ve been monitoring my tank parameters closely and noticed that my phosphate levels are consistently around 0.90 ppm and nitrates are fluctuating between 40–55 ppm, measured using Hanna checkers. Lately, I've observed very slow coral growth, and some corals like Goniopora and a...

My tank chemistry got messed up in a matter of 2 days out of no where Mag: 1130 Alk: 12 No3: 1 Po4: 0.07 Ph: 8.3 Ca: 200 I will do a 40% water change tomorrow Please give me some tips on what to do to fix this high alk while increasing calc I was dosing all for reef I had one of my wall...