I use a hydrometer to check my salinity for my water changes. I was placing an order from Marine Depot the other day and decided I would order a second one just as a "check." I got the Instant Ocean hydrometer and went to check my salinity last night . . .
My original hydrometer read 1.023, right where I want it. This new one read 1.031!!!!! Needless to say I was a little shocked. Now I don't know what to do. I have always felt like I had to add more salt than the directions said, but I figured I was just miscalculating.
All my fish are nice an healthy. So I have 2 questions:
1) What are the effects of high salinity on fish?
2) Should I bring my salinity down to the appropriate level based on the readings of the new hydrometer?
Looks like it might be time to invest in a refractometer!!