how do u calibrate a hydrometer?

are you referring to a float or a swing arm hydrometer.
i have only used swing arm hydrometers, and to my knowledge they are not calibrateable, not are they terrible accurate anyways.. what you might want to look at is a refractometer, these are calibrateable, and very accurate.

The only way I know to calibrate a hydrometer would be to find someone who has a refractometer, and test some water against each other, and make your own markings on you hydrometer. I havent tried this so I dont know how effective it is though.

The only way I know to calibrate a hydrometer would be to find someone who has a refractometer, and test some water against each other, and make your own markings on you hydrometer. I havent tried this so I dont know how effective it is though.
pballafreak :welcome: to Talkingreef

i would like to say, this is great to identify how accurate your hydrometer is, but is not a calibration, calibration would involve identifying the variance and then tuning the instrument to be accurate. i am not aware of anyway to perform that adjustment

thank you for your help

thank you for your help
no problem, if you need anything else, please let us know

Hi pballafreak.

:welcome: to TR.

Please do yourself a favor and return the hydrometer to the store if possible and purchase a Refractometer from Marine Depot for $50.00 takes a simply 2 second calibration and the accuracy will be more beneficial then taking chances with the hydrometer. Trust me I ran my hydrometer over with my car. :-)

Mark- Welcome to TR!! ;)

The only way I know to calibrate a hydrometer would be to find someone who has a refractometer, and test some water against each other, and make your own markings on you hydrometer. I havent tried this so I dont know how effective it is though.
I use both refractometer and swing-arm hydrometers. I use the refractometer to calibrate and to sometimes double check my hydrometers. Once you know how much of a variation that the hydrometer has, it works fine.

BTW, welcome to TR

well i got a refractometer. how do i calibrate that? i need distilled water or something?

yes, use distilled or RO water.

place a few drops on the lens as indicated.
it should read right at the bottom line 1.00

if not, you should have a small screw in the side to adjust it to 1.00

well, the wicked ways of the swing arm are numbered and replaced with a telescope thats able to see mars's ice caps

thanx everyone the refractometer is working. my hydrometer was saying 1.026 but it was actually 1.030 so another believer.