I became a pool owner a couple of weeks ago and I've been learning, testing, balancing and everything seems to be going well. The salt cell was very scaled so I cleaned it (with guidance from TFP.com) and over the past few days FC jumped to 6.5. I've reduced the pump run time and SWG % to let it come back down to the 3-4 range. I've been using Pool Math but hadn't looked at CSI until today. Right now my levels are:
I haven't tested for borates but entered 0 in pool math. Water temp is 52F. According to pool math my CSI is -0.2 and it says that is balanced. So far so good. When I enter target levels that I got from the Water Balance for SWG page in Pool School:
CH 250 (I've been told CH will rise some due to evaporation)
And add current salt, borates and temp
Pool Math says my CSI will be -0.71 and it says corrosion of plaster likely.
I'm not trying to get my TA down to 80. However, I have noticed that I have to add acid to lower the pH about every other day and that wasn't happening as often before I took over the pool so I assume with more consistent dosing of acid the TA may drift down some over time. Assuming TA will drift down to 110 and pH will usually be around 7.6 pool math says my CSI will be -0.42 and it says that has the potential to be corrosive to plaster.
My questions is, should I be concerned? If so what target levels should be adjusted?