I agree with bigbella in general, but there is one exception to the rule that has been observed. In Berkeley, CA (University Ave, can't remember the name of the shop), there is a hydroponics store, and they are growing the biggest cephalotus I've ever seen. It has never been transplanted, and has been there for a good 3-4 years, and has way overgrown it's 3" pot. All they do is water it with DI water! The plant has never seen daylight, and has always been growing on strong artificial lighting, 24/7! It has never been fertilized-only relies on bugs in the shop, which it has plenty of.