Float pods(or sensory deprivation tanks) contain 1200 pounds of Epsom Salt dissolved in 10-12 inches of water. This silky solution is kept at body temperature. Once inside the tank, all you have to do is lay back in the warmth, in the silence, in the darkness, and do nothing.
Floatation REST (Restricted Environmental Stimulation Therapy) is likely to be the most mysterious and calming thing you've ever experienced. Escaping all stimuli, the mind drifts into the deepest possible dream-like state of relaxation. Your brain releases an abundance of 'feel good' chemicals and your body begins reducing tension and fostering healing.
One hour in the tank is equivalent to about four hours of deep sleep. This is one major reason people float. Some others are to relieve stress, accelerate recovery, fight addiction, eliminate chronic pain, lower blood pressure, maximize training, to reduce/eliminate the effects of jet lag, and as a reprieve during pregnancy.
In short, floating frees mind and body of external stresses in a unique weightless environment allowing mental and physical energies to be conserved and directed and revitalizing you.