Advice to *anyone* who uses a maintenance service.  Check references.  They are not all as good as another.
	
	Test the water yourself, regularly.  You should receive a written report each time with parameters and observations as well as a description of work performed etc.  If you don't, find another service - don't even waste time asking why they didn't.  Do test to make sure the results are consistent.  Trust - but verify.
	
	Speaking from direct experience, I can tell you that a LOT of so-called services don't ever bother to test - and I even wonder if some have even changed water :-/  It's an unregulated industry so there are not set standards.
	
	Not naming names or singling anyone out - just a suggestion. Over the years I've seen and fixed some real messes where somebody paid good money for 'maintenance'.
	
	Jenn