We are in Gulf region. In the summer temperature will rise upto 50degress there by the water also will be too hot. V have two ground water Tanks (each of capacity 4000 USG ) and 6 over head tanks (each of capacity 600 USG). We have to use the water for drinking as well as other uses (washing, bathing etc). So please suggest a feasible cooling system to have the cool water (18 to 22 Degrees).