The acidophilus will have a much better chance of thriving if you take live culture FOS (fructooliosaccharide). Taking the FOS actually replenishes your intestinal tracts naturally occuring flora, and makes it easier for the acidophilus to thrive and destroy harmful bacteria. It will also make it easier for your body to assimilate the nutrients from the foods you eat. A colonic won't necessarily destroy the good bacteria. One of the questions you'll want to have an answer to is whether or not the colonic adminstrator is using plain tap water. If they are, then you will have beneficial organisms destroyed by the chlorine and other additives. A colonic will help flush out the putrefied matter that parasites thrive in, and make it easier for the beneficial bacteria to reproduce and flourish.