Do I need a Temporary Resident Permit on a tourist (L) visa , if I stay less than 30 days ?

I have an L, multi entry, 1 year , 30 days per entry. I would like to stay for 30 days at a time without working or studying. I am retired and can prove sufficient funds , I just like living in China . Is it possible or is there some trick to it .
Thanks , STEVE