I don't know what kind of kidney problems you have, but I had a kidney infection that was very persistent. At first I wondered why so many symptoms went away from doing UT, but the kidney infection kept returning. Then around my 3rd or 4th month on UT, the infections stopped completely and I don't get them anymore.
That's the funny thing with this practice. All your ailments don't go away at once. They go one by one, or at least that was my experience. Do UT every day. Skipping days on UT is like being on much needed medication and skipping that. It just doesn't work as well if you skip a day or many days at a time.
If what you are getting are kidney infections like I was, drink lots of water. You may want to stay away from Liver Flushes while you are having kidney problems because the epson salt dehydrates you too. When your kidneys are feeling strong, then do them:) There is a kidney cleansing tea that Andreas Moritz recommends.