from what i know:
chillers chill your tank but not your house (at least in the room where chiller is)
chillers generate lots of heat, so if you want to use a chiller, be prepared.
cooling fans however won't cause much heat in your house, but not that effective as chiller.
cooling fans cools to 26degrees while chillers can go beyond that.
cost wise, chillers are expensive, but fans are cheap. electricity costs are high too.
these are some factors that you may consider before choosing.
IMO, cooling fans are pretty good enuff.
experts, correct me if im wrong