The Hanna Salinity Tester works fine, the problem is the user.

[@GwonkReefkeeping]

You are 100 percent correct. I love mine. I just had to realize that I had to keep it calibrated. I would probably say not going more than a month or two without recalibrating.👍🏾

[@lkapitan8232]

Exactly right, about a month for mine.

[@hakman239]

My refractometer showed 1.025 Hannah showed 1.023 and was calibrated over week ago but I calibrated my refractometer then checked it again with the fluid the reefractometer lost calibration without knocking it or anything

[@lkapitan8232]

I kept having differences in my equipment also, so I bought the Tropic Marin Precision Hydrometer, It cannot be wrong with normal temperature ranges and took out all the doubt, highly recommend

[@spicyreef]

w/ me u can pop that up to 100% 🙃

[@filipinoreefer]

Test compare with refractometer and hydrometer. I have tried to compare all and they don't match. Please make a video I need help on that.

[@lkapitan8232]

Since a refractometer can be calibrated, I would take that as a standard. The hydrometer should be close, but may not be exact. What it should be is reproducible as in, your refractometer says 1.025 and the hydrometer says 1.024, that's OK as long as it always has an offset of 0.001. Did that make sense?