Poolside, Inc.

I have been using Poolside for over ten years. Maintaining a pool is a complicated process. Procedures and chemical balances must be precise in order to extend the life of the equipment and the pool itself. Chemicals must be introduced in a certain way at certain times in a certain order. Doing everything right saves time, money and insures swimmer comfort and safety.
I can only assume that the bad reviews are left by people who don't know what they're doing, guess at it then get frustrated when their desired result is not achieved.
I go to poolside several times a month to get my pool water tested, to pick up supplies and to discuss pool water situations. I have never interacted with an employee who didn't know what they were doing other than the occasional student summer help who, upon an issue, would call upon the manager who seems like she lives there and who is a flat out pool expert.
My pool is always crystal clear and enjoyed by the family from April through October thanks to Poolside's expertise.
If you don't know what you're doing, consider hiring their techs to maintain your pool for a season or two, work with them, learn from them then do it on your own. Going on the cheap costs more.