I would recommend you start getting your own RODI system. Never trust the LFS their salt will always be low. I have tested a few local ones here in San Diego and they have been low 1.021-1.022. If you have fish only I guess its not that bad. It is better to have control and mix the salt brand you want at the specific gravity you want. Do yourself a favor and test the specific gravity, Ca, Mg, Alk, and Phosphate. If they allow you to test the tds of their RODI check that too. You will see why many of us make our own plus you need to top off after evaporation to keep your salinity stable.