I live in Dubai, and the water for my whole house is stored in a water tank on my roof. This is a problem as during the summer months the temperatures reach up to and a bit beyond 50 degrees in the day, this heats up the water in the tank alot so we don't have any cold water during the later part of the day. I wanting to implicate a passive water cooling system on my house where a pipe comes out of the tank and into the ground (I live in a bungalow so it's not too much of a problem) and down into the ground where it's cooler. I'd then run this pipe around underground which will cool down the water, then bring it back up into the house. I am desperately looking for help though. I want to investigate all of the variables and try to come up with best system for my house. I'll need to investigate things such as thermal conductivity of the soil, the equations for the pump that I want and what the best pressure/water flow would be as I'm not too familiar with water systems like this. I'd love detail and how I'd carry out the experiments, its a really open project and I'd like to measure/calculate everything. All the help would be useful.Thanks alot!