I checked my calcium level today, expecting it to be low, as apparently high alkalinity usually equals low calcium. But it was high, at 480-500mg/l. I tested the seachem test with the reference, and it was a bit high, putting my alkalinity at about 5meq/l. My ph remains relatively low at 8.0 (lights on,11pm) just after a 25%PWC, and slowly goes down over the two weeks until my next PWC.
Can anyone help? Why do I have high alk and high ca? I dont dose anything. I have 2 hard corals, 3 soft, 1 shrimp, 4 hermit crabs, 2 turbo snails, and a bit of corraline algae growing. Shouldn't my Ca be normal/slightly low, rather than high?