Hydrometer vs Refractometer

[fishoholic]

Originally Posted by ElGuappo

correct me if im wrong as i dont have a refracto and i have used a friends to find out my hydro is out .0015 aprox. but are you not supposed to use distilled water to zero in a refracto?????/

Yes, distilled/RO/RODI, is what I've been told to use and RO is what I've used for calibration purposes.

[Red Deer Reptiles]

yes you can use ro water to calibrate remember ro water is at 0 so look in your refractometer if its not at zero adjust the screw to bring it to 0 been doing for 10 years.dan

[Red Deer Reptiles]

we suggest in the future have the store where you buy your refractometer calibrate it for you hope this helps.dan

[JDigital]

Your refracto should have come with calibration fluid, I got mine at Red Coral too, same one, and mine came with it.

[new but handy]

I've got the Sybon refractometer it came with a bottle of ultra pure water for calibration (water-- 0% anything +/- o.o1ppt) It's actually called "ultrapurewater"!
It seems to do the trick, although I've never tested it against anything else

[Hairytank]

Yes, I used the "ultrapure" water to check the calibration and it was right on the money. So, if that (0.0129) is an acurate reading, which I think it is, then I will do some slow changes to the water.

[mark]

seen this poll?

http://216.187.96.54/vbulletin/showt...=Refractometer

[fragNplug]

After reading this i guess its time to get one myself, im scared at what mine really is now.

[Johnny Reefer]

I have both, but haven't used the hydrometer in about 3 years. I always use the refractometer and will continue to do so. But a question comes to mind....if the error of a hydrometer is known, could the hydrometer not still be used and just simply apply the error in calculating the true reading?...or is an error in a hydrometer prone to fluctuate? (This is assuming the instrument is cleaned thoroughly after each use).

Cheers,

[Red Coral Aquariums]

A refractometer is possibly the most important initial piece of testing equipment you can purchase.
We have sold many hydrometers but always recommend the refractometer.

I have found that only approx. 5% of new hydrometers are accurate but once you find out how much they are off they (under proper usage) remain consistent. We test hydrometers going out of our store and they are an average of .04 out but have had numbers of .1.

Kevin