OK ----------
Your CSI is not in the aggressive region because of your TA and pH. Maintain a CSI of greater than -0.6 by not lowering your pH any more than to 7.8 when, and if, it reaches 8.
As the water warms, your CSI will naturally become more positive. So as your TA falls by adding acid to maintain your pH at 7.8, your CSI will be OK. Over summer, your evaporation will mean you are adding high CH fill water and thus, your CH in the pool water will rise. I suspect, by July, your CH will easily be 300 ppm.