Oct 22, 2021 · Since getting into the hobby, I've been down the rabbit hole on salinity/specific gravity measuring devices. I've had the Hanna HI98319 Salinity Pen, a $20 Amazon White-Label …

Oct 10, 2023 · A refractometer does not read accurately when alcohol is present. Fortunately, the equations for conversion to SG numbers are pretty accurate within 0.001-0.002 gravity units as …

Nov 16, 2011 · A refractometer measures the refraction of light. Alcohol skews this, so the reading is useless once alcohol is in the mix. The hydrometer reading would be the correct reading if …

Jul 26, 2016 · Refractometers And Salinity Measurement Salinity is one of the most important parameters measured in reef aquaria. It controls not only the salt balance between an organism and …

Dec 10, 2015 · How a Refractometer Works There are several types of refractometers, but this discussion will focus on hand held refractometers because reef aquarists rarely use any other type. …

Jul 12, 2018 · A refractometer is likely a better choice than a hydrometer. Before the hydrometer crowd jumps in and claims that you can get perfectly good results using a hydrometer too, yes, that's also …

Jul 21, 2006 · I made a solution of 3.65 grams sodium chloride to 96.35 grams RO water to calibrate my refractometer. When I put it on my refractometer do I dial the refractometer until it lines up with 35 …

Oct 23, 2018 · The instructions on my VEEGEE refractometer specifically calls for using distilled water for calibration. There are some true seawater refractometers that require distilled water for …

Jan 21, 2018 · I have a refractometer from brs with calibration fluid. I have to calibrate before every use as it usually needs it. Even from one day to the next. I've gotten to the point of double checking …

Nov 21, 2025 · If you mean the refractometer, it depends on the quality of refractometer you buy. But my $30ish one tends to hold calibration for a while, as long as it doesn’t experience any big temp …