Sadly, you were "Pool-Stored". It's happened to all of us, leaving us sadder, but wiser. The K2006, K2006c, and Leslies Chlorine FAS-DPD Service Test Kit are all great tools. All basically the same (the "C" has larger amounts of test chems, Leslies is a re-branded K2006).

However, in their defense, they probably just read off the liturgy of recommendations provided by Biogard or someone else, without knowing, say, that calcium is USELESS in vinyl pools.