Glad this was found to be the top off being SW..
Just want to say incase others see this with a similar issue -- but cause not known, I have had my refractometer go 'weird'. For the life of me I can't figure out what happened, but it showed an extremely low reading on new salt water. Checked tank, also very low. Checked calibration fluid, also low. Checked RO water, also below 0.
I had been on vacation and asked the tank sitter if he had 'played with it', nope.
Oddly enough after recalibrating it, and generally matching tank salinity to new water.. it suddenly went *back* to 'right' which now showed everything higher than expected. Including calibration, and RO water.
I have no idea how or why this happened..
Guess only point is to exercise caution when a tool shows an unexpected reading instead of diving into instant action
--probably a good time to plug the idea of weighing salt.. also helped me question that validity of the tool knowing i had weighed the proper ammount so no way it be 1.010 like the tool was saying.