I could really use some insight on why my nitrates are consistently around 20 PPM while my phosphates stay low between 0.05-0.08 ppm. I do weekly 10% water changes, have a biopellet reactor, and refugium section (although my chaeto won't stay alive even with a good kessil fuge light). I do have a small bag of chemi-pure in the sump. I doubt it's overfeeding because why would my phosphates stay so low? Any insights appreciated.
Water parameters:
SG 1.025
Alk 8
Ca 450
Mg 1280
NO3: 18-20
PO4: 0.05-0.08
Water parameters:
SG 1.025
Alk 8
Ca 450
Mg 1280
NO3: 18-20
PO4: 0.05-0.08