Hydrometer vs Refractometer

[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