On Sat, 12 Nov 2016 19:20:14 +0000, John Rumm
wrote:

What was your suggested solution?

Return the cold water tangentially to prevent the mixing, the colder
water then inducing a slight vortex and falling to the bottom, any
warmer water at the same level would be less dense so would rise and
not tend to move past the denser colder layer from centrifugal effects
as long as there was little turbulence. Hot take offs were already
from the centre of the 3000litre cylindrical tanks.

AJH