Re: enema
Hi iowabee, for safety I don't recommend inserting a colon tube more than 6 inches.
The reason to use salt in the enema solution is to prevent the dilution of the concentration of electrolytes in your body. The salt solution of the enema is just about the same concentration as that of the cells in your body. As a result, the enema water is neither absorbed into your body, nor is water removed from your body into the colon and released during the enema.
So the concentration of electrolytes in your body does not change during the enema, which is what you want.
A standard salt solution (1 teaspoon to one pint of water) is called isotonic, meaning that water doesn't cross the membrane between the colon and the surrounding cells. Look up osmosis in Wikipedia where they have a good explanation about this.
Hope this info helps, Valerie