Sg in relation to Ca, Mag

Triggerjay · Jul 6, 2015

hey Randy. I was curious if there is a cooralation between SG, Ca, and Mag? Reason I ask is I hadn't checked my SG for a while. Checked it two days ago and it was 1.022.... My calcium was 450 and my mag was 1500. Over the last two days I raised SG to 1.026 and today CA is 575, and mag 1700. Alk held steady at 10. These readings were using a refractometer and NYOS test kits.

Randy Holmes-Farley · Jul 6, 2015

Yes, as you raise or lower salinity, everything we measure in it (except pH and ORP) will rise and fall in similar proportions (assuming it is in the salt mix).

So raising sg from 1.022 to 1.026 will raise everything by about 18%, which would push calcium from 450 to 532 ppm.

Triggerjay · Jul 6, 2015

Thank you randy. The 575ppm Ca was an estimate as my chart only goes up to 500. At 10ml reagent used, ca is 500. I used 11.5ml. On the scale from 9.5ml-10ml was a 25ppm jump, so I based my result on that.