You're using CaCo3 to measure alk so the numbers you see around may seem odd as most use dKH. Currently you're sitting at 240 CaCo3, 4.8 meq/L, or 13.41 dKH depending on how you want to read it. Your alk should be 143.2 - 179 CaCo3, 2.86 - 3.57 meq/L, or 8-10dKH.
Test your calcium and...