I've mastered all of the usual challenges associated with owning a in-ground swimming pool for the last 20 years, i.e. chemistry, opening / closing, etc. Of course, at the begining of the season, a heater helps to bring the temperature up to a comfortable range (83 - 86 degrees). Now, however, a succession of hot, sunny days in Georgia have increased the water temp. to
90 degrees which is not all that refreshing. Therefore, the problem herewith submitted is: How to lower the temp. of 24,000 gallons of water, 4 - 7 degrees, in a reasonable, economical way. BTW, using ice or dry ice is not feasible. Simple physics calculation show that rather large amounts would be required, (like 750 lbs. of ice). Also, please do not reply with a suggestion I visit the local pool store to ask advice or "Google" for info. I've exercised the obvious options and am looking for real solutions from clever, experienced folks like the ones that visit this NG.Thanks in advance.