I'd appreciate any comments regarding the following prosaic/practical questions on inground swimming pool water...what the heat transfer mechanisms might be. (1) Does a dark vinyl liner aid in warming pool water any more than a light liner? (I'm guessing it might but with roughly three ft depths at one end and about 8 ft at the other end I'm unsure how much infrared sunlight energy makes it through water. Nor do I understand how that energy is transferred directly to the water than than via the liner.) (2) We had to cut off about two feet from the end of our pool cover blanket, (due in ultraviolet deterioriation) which is thin plastic bubble type material, that floats on the surface and helps contain heat during cool evenings. So now there is about two feet of pool water surface exposed for the width of the pool. Which will retain heat the best: leaving the open portion of the blanket at the deep end or the shallow end? Why? (I have no idea on this one but it would seem as surface water cools at night it likely slowly sinks and sets up convection currents. Maybe the shallow end would cool faster and hence lose less heat to the air but this does not take into account the underwater transfer of heat between warmer water under the blanket and cooler exposed water...) (3) Does anyone know if pool water warms faster in direct sunlight with the pool blanket on or off? Believe it or not manufacturers don't seem to say anything about that. (This would seem to depend in part on ambient air temperatures so maybe this question should be limited to those temperatures where air is at least as warm as water..that way little heat loss from water to air would occur.) Appreciate any thoughts or insights.