DJA, I ran your numbers in Poolmath and I'm getting a CSI of -0.26. Not sure about the -0.5 you saw. So it looks like you are sitting well. As for the recommended levels you noted, you have room to the left/right for each parameter which can help bring your CSI closer to neutral if you're really worried about it. You can view those levels on the
Recommended Levels page. Water temp is our biggest challenge this time of year, and that won't be an issue soon. If your local water is hard, your CH should climb back to the 350 (minimum) this season, So you can wait on that and simply let your pH and/or TA ride a little higher to compensate, or simple add a little calcium. But if you do add calcium, I would shoot for the minimum 350 range. Don't go too high or you'll have a higher CH than you need. And as soon as your water temp gets back to the 80 range, your CSI will climb very fast. As Dave noted, CSI has it's applicability, but we are careful to not get too wrapped around the axle on it. As long as you keep your numbers in those recommended ranges you should be fine. Lastly, please show which city you are from in Texas. As you know, the weather impact on pools varies from N, S, E & West.
More about CSI here:
Calcium Saturation Index