How are you checking salinity?

[corey01]

Professional Automatic Temperature Compensation Sea Water Salinity Refractometer for Aquarium, Hydrometer, 0-100ppt & 1.000-1.070 Salinity Specific Gravity https://www.amazon.com/dp/B00AZ1SMC2/ref=cm_sw_r_cp_apa_wFakAb27GPM7T

This ok?

more or less exactly what I use. From what I have seen from the cheapest to the most expensive there's not a lot of difference. until you get to the digital ones anyway. but just my opinion.
the key Is to calibrate as close to your reading point as possible. so you would want to get some 1.026 calibration fluid. I like to keep the fluid and the refractometer in the same place so there's not a huge temp difference when calibrating.
if you google Randy Holmes refractomer, you should see quite a lengthy nice article on calibrating, function and proper use.

 

[drawman]

+1 on the refractometer. Pro tip is to keep it calibrated.

 

[Robink]

Don't they come with the calibration stuff?

I bought the calibration fluid and still off. So I just double check weekly with refractometer and keep my new water on point.

 

[Jongalt26]

As mentioned before, a refractometer is a must along with calibration fluid. Be sure to calibrate every day of usage until you get an idea as to how many days can go between calibrations.
I dont know if it was mentioned before, i scanned the posts but didnt see it so i apologize if it was, and thats the wait period from when the sample was placed on the refractometer to when the reading should be taken. This can make a couple points of difference. This is also tedious when making new saltwater, constantly having to retest until the SG is correct.

That leads to my recommendation of the pinpoint salinity monitor. It has a much higher resolution and is very easy to use. Just drop it in and less than a minute later the reading has stabilized. Great for tossing into your SW mixing barrel. I found the error deviation to be more favorable than other electronic devices too.

 

[Idoc]

do you guys use calibration fluid often? many people i know complain and use ro water.

Calibration fluid is cheap... around $6 and it only takes a couple drops each time! Its always better to calibrate anything closer to the standard you will be measuring. So, better to calibrate to 35ppt than try to calibrate to 0ppt.

 

[Jongalt26]

Calibration fluid is cheap... around $6 and it only takes a couple drops each time! Its always better to calibrate anything closer to the standard you will be measuring. So, better to calibrate to 35ppt than try to calibrate to 0ppt.

It is also not quite a linear scale, so calibration at 0 can be off at 35%

 

[lbacha]

Apex monitor with a refractometer for weekly checks of the probe

 

[jbow50]

Refractometers

Petco has one for under $30

I got mine for $20 on Amazon and a bottle of calibration fluid from brs for $5.

 

[Robert Vacchiano]

Swing arms will always be unreliable when the get older .It does not matter if you clean them with vinegar they will be off it’s just a matter of time .Alwas cleaned mine and it read 1025 it it was really 1030.

 

[kamike91]

two things I wont own in saltwater

an ammonia test kit or a refractometer

swingarm is plenty good, or nobody would have got through the 90s

make that three things, a nitrite test kit.

I've used the same swing arm for 20 years without replacement until I dropped it and it broke. I finally bought a refractometer, but the type of livestock I keep now are far more sensitive to parameters as well. It all depends what your keeping and how much variability you need to control. For this reason I have a bunch of test kits including nitrate and ammonia. And hmm... they always read 0...so maybe you're right, I probably didn't need them lol.

 

[Randy Holmes-Farley Verified Community Expert]

I prefer conductivity measurement for measuring salinity.

Quick, easy, continous reading of salinity and temperature (as in acclimation situations), and has uses no other method is good at, such as measuring the potency of limewater.

 

[MaiReef]

How often do the conductivity probes need to be calibrated?

 

[Aaron J Henning]

Milwaukee MA887 Digital Salinity Refractometer

 

[Randy Holmes-Farley Verified Community Expert]

How often do the conductivity probes need to be calibrated?

The Orion Model 128 (high quality, 4 electrode conductivity meter) that I used for years was not even capable of altering the calibration. Every time I checked it for years, it read a tiny bit lower than the commercial standard claimed to be. I also did not notice much drift in the Pinpoint that I used.

 

[Randy Holmes-Farley Verified Community Expert]

Milwaukee MA887 Digital Salinity Refractometer

I've been seeing an unusual number of folks checking that refractometer with an Aquacraft standard and getting results that suggest either one or the other is not working correctly. I'm not sure which is the problem, but I'd lean a bit toward a standard solution problem from Aquacraft:

https://www.reef2reef.com/threads/calibration-solution-wrong.341283/#post-4250628

 

[jd371]

I use both a Refractometer and the Milwaukee. I have the Refractometer in my mixing station to use when I'm making water for a wc. The Milwaukee is in my workshop where I test the water.

 

[Tyler_Fishman]

There s no perfect way to test salinity with simple devices at our homes, we are in the ballpark most of the time never 100% accurate even with digital refracrometers, but refractometers are a heck of a lot more accurate than swing arm hydrometers

 

[PiscesPower]

Milwaukee digital. I calibrate once a month.

 

[Sealion]

Refractometer for me. Also I made my own saltwater test solution. It's easy if you have a gram scale. 3.35 grams of salt and 96.65 milliliter soft RO/DI water. Should come out to 1.0267 on the refractometer.

 

[3mm3]

Refractometer here. Will not use digitals the margin of error is too great for me.