To keep my water resevoir temperature below 70°F, I use frozen water bottles with a twisty tie around the neck. That way I can hang it on the side of my bucket and I don't have to reach into the water to get it out. I swap out a bottle every morning, and every evening.
Nice work! commend you for going for a photoperiod strain for your first grow.. wish I wouldnt have wasted months dabbling in the autoflowers. curious to see how this ends up, good luck!