An intense or long warm-up in hot weather isn't a good idea. Every farm pond doesn't need lime. Ponds that need the addition of agricultural limestone are the ones that still have a low production of phytoplankton after fertilization. When pH of the bottom mud and the total hardness of the pond water are low from a shortage of calcium carbonate, any phosphate you add as fish-pond fertilizer won't be as available to provide nutrients for microscopic algae growth. A good indication is the lack of plankton bloom even though you've regularly added fertilizer to the pond.
Winter is the time to add lime to ponds.
It will go into solution and be available when you begin fertilization again as water warms in the spring. If you apply lime during the summer, phosphate in the pond water will precipitate out and be temporarily lost to the nutrient cycle. Pond waters with total hardness greater than 20 ppm seldom respond to the addition of ground limestone. Also, when mud-water pH exceeded 5.9, total hardness usually exceeded 20 ppm. So the pond needed no lime.