Ah ok, not familiar with that store. I was just gonna bring up something that happend a few weeks ago.
Christy was having more algae problems so she used my TDS meter to test her R/O water.. it was 29ppm which is way high!! The water was bought from Save On. I guess they haven't changed out the R/O in a few years!
She tested tap water and it was 25ppm.. to think people pay for that R/O water
So phosphates could be comming from that water source or maybe the salt mix?