Bob I really don't think you should recommend for people not to do water changes when you have nitrates of 160+ in your own take. I totally disagree that no water changes makes for a more stable tank, in fact the opposite is really true. You still need to do water changes with a sandbed but more like 5-10% every week to every other week, and you don't have to vacume out the sand like you do cc. You wont be sorry with the change.
As was stated before, you can change your cc to sand just by scooping out the cc and replacing it with sand, you may want to remove some of your water (and save it in buckets) just to make it easier to work in the tank. If you are still in the process of cycling then you don't have to worry about anything. What method of cycling are you using? Be prepared for a very cloudy tank when you add the sand (especially if you are using aragonite sand) it should be clear within a week, the cycling will help it settle down.
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