::POLL:: How far off is your plastic Hydrometer ::POLL::

[scaryperson27]

Essentially the title says it all. If you have found accurate results that conflict with your Hydrometer, how far was your hydrometer off?

If you want to list the brand and the poll result in a post in this thread, by all means do so!!

[Fish_wiz2]

instant ocean hydro rinsed after words, +.001 to .002 off. checked with refract which i am too lazy to use

[Reef Newb11]

i didnt realize how off it was till i finnally bought a refractometer and found my salinity to be 1.031...yet the swing arm was right on 1.026

[scaryperson27]

Shows how valuable a good refractometer can be.

[Thoro]

Yea those hydrometers are junk when I first set up my tank thats all I had and for some reason my hydrometer was calibrated to measure salinity at 69 degrees, which makes no sense because we keep are tanks well above that temp.

when I got my refractometer I realized my hydrometer was off by at least .005 good thing I only used my hydrometer on setting up my tank before I had anything in it.

I would suggest everyone get a refractometer thats new to this hobby it makes keeping your salinity dead on and gives you ease of mind for sure.

[James77]

<a href=showthread.php?s=&postid=14337557#post14337557 target=_blank>Originally posted</a> by Reef Newb11
i didnt realize how off it was till i finnally bought a refractometer and found my salinity to be 1.031...yet the swing arm was right on 1.026

I had the complete opposite happen to me with an improperly calibrated rafractometer. I was calibrating it as instructed in the instructions(few years ago)using RO/DI water. I was having progressively worse coral response in my tank, and found the salinity to be 1.034 ish using 2 different float hyrometers and one of the glass floating hydrometers.

I have no doubt that refractometers are far more accurate and reliable than floats, but they must be calibrated properly.