I just bought a clear, 12 mil solar cover for my pool and put it on for the first time yesterday evening. The water temp was 80 when I went to bed, and this morning it was still 78! Losing only 2 degrees is an amazing improvement since I usually lose 5 or 6 degrees each night. Every degree is a big deal for me because I live in a wooded area and the pool gets a lot of shade. The warmest my water has been this year was 82. The warmest it's ever been was around 84-85 during massive heatwaves.
My first question is about leaving the cover on or off during the day. I've read that leaving the cover off will probably heat the water faster than leaving it on if it's warm, sunny, and not too windy. But how windy is too windy? Today is forecast to be sunny and warm (high of 89), but with 10 mph wind. And, if this is a factor, there will be low humidity (30 - 40%). I'm wondering what's the best thing to do on a day like today. It may not make a huge difference either way, but even a small increase in temperature can be the difference between my skinny kids getting blue lips and leaving after 20 minutes, or staying in and enjoying the pool.
Question #2 is about chlorine loss. I know that the cover will keep the chlorine in my pool longer. I'm going away for a week and my plan was to bring the FC level up to about 18 with liquid bleach before I go. I lose around 2 ppm daily, so I figured I'd be around 4 ppm when I get back. My CYA is 30. Since I just put the cover on, I don't know what to expect for FC loss now. Should I stick with my original plan, or put in less chlorine before I go?
Thanks in advance!