calcium

  1. D

    Pea sized black spot

    Hello Fellow Pool Boys and Girls, We just finished building our pool about a month ago. Unfortunately, we've developed a pea sized spot with a black center and brownish cloud moving away from the center. I tried placing a chlorine tab on the spot, for approximately a week, and brushed...
  2. Chemingway4

    New to TFP (Kind of) Question about CH after Pool Refill (pool store didn't want to sale me anything!) and daily Chlorine loss

    I recently drained and filled my pool (3 weeks ago). The CH reading is 80ppm. I know that's low, but when I went to the pool store to get supplies, I was told not to worry about the CH as it would slowly rise over time. I thought it was odd that they didn't want to sale me anything, so I left...
  3. R

    Calcium hardness and salinity for salt water pool

    Hello all, I’m new here to the site but not to pools. Grew up with a chlorine above ground pool, bought a house 5 years ago with a 25,000 gallon in ground pool that I converted to salt a couple years ago. Today I had to add 25 pounds of calcium chloride to increase my calcium hardness. Since...