I have a 120 saltwater tank with a Hiatt Filtration system. Ammonium 0, calcium 500, nitrates 0, alkalinity 7.4 dkh, salinity 1.023, phosphates 0, and ph is 8. I have a total of 8 fish, 100 is snails, 2 cucumbers, 2 sand sifting stars. I have a couple of different issues but the big one now...