I have an above ground pool(unfortunately not purchased from Hot Stuff). The staff at Hot Stuff are very knowledgeable about the chemicals and are more than willing to help me with any problems. The best purchase to date has been a glass filter system for the pool. Cost a little up front, but what it saves in chemicals and filters more than makes up for it. I wouldn't go anywhere else and when this pool gives out my next one will be bought from Hot Stuff