Survey

[TechGuy]

Where did you buy YOUR Refractometer??

Aquatic Specialists...

[harleyrider]

Scott, there have been a few threads on RC about this.  I forget the reasoning, but just calibrating at zero isn't a safe idea.  I heard some people getting like 32...that should've been getting 35 when they just calibrated at zero.  I dunno.

I was just reading a mfg post about calibrating and they say you can do with distilled water or the stuff in the bottle they got, but with distillled water it can POSSIBLY be off a little, and they recommend usings the calibration liquid.

[slandis3]

refractometer, got it through marine depot.

[Riderc82]

Looks like this thread is dying so...  Whats more accurate a monitor or refractometer?  Also how often does do you have to change the probe if you use a monitor?

[TechGuy]

Looks like this thread is dying so...  Whats more accurate a monitor or refractometer?  Also how often does do you have to change the probe if you use a monitor?

I would buy a refractometer. Its cheaper, and mechanical. Electronics can fail. In the end, nearly all of these devices are resistance based, hence the need for calibration. And resistance is such a touchy thing.

[atreis]

I agree with Tech40Guy, even though I use a digital salinity meter.  All else being equal, refractometers are more accurate.  I had a horrible time reading it though, so figured being pretty-close with a salinity meter was better than mis-reading a refractometer.

[TechGuy]

I have a hard time reading refractometers.

So I say this.

Check it against the old swing arm meters, and be your own judge. I found mine to be off a tad less than 1PPM.

But I think the best test is this. Checking with both on a regular basis, and above all. Watching your livestock for changes. They are the best test kit available for all situations.