Salinity measurement face off! Hanna, Milwaukee, Neptune

[wangspeed]

First, let me say this. I hate analog refractometers. My experience is that they go out of calibration if you look at them. Yes you can calibrate each time, but that’s a pain. Also, reading them isn’t exactly clear. Where is the line? It’s fuzzy, so which part of the line do you count as your measurement?

A long time ago, I switched to the Milwaukee MA887. I love it, except for one thing. It is very consistently +.002 SG. It always has been right out of the box. During DC MACNA I spoke to someone at Milwaukee about this and he was super defensive and rude. I found out their calibration standard is different than normal. I got a bottle of it and sure enough, it reads what it says it should. IMO it is -.002 SG from other standards that should be 1.026. I have tried every standard I could get my hands on. It is always +.002.

Strangely, a friend of mine had the Hanna version of this same checker and it is dead on accurate. Maybe Hanna calibrates it with different fluid.

I finally came to the realization that this is fine as long as it is consistent, and it is. It doesn’t lose calibration. Ever. Not a single time that I have tested it has it been off. I’m willing to sacrifice accuracy for this kind of consistency.

Along cake my current tank build with a new 2016 Apex. It has a conductivity probe. Nice! Except everyone complains about it being off. Not mine. Mine doesn’t do wonky things. It reads a little on the high side though.

Just a few weeks ago, I saw the Hanna salinity checker announcement. I guess they retired the old version that is almost identical to Milwaukee. Being a gadget person, I decided to get it. Besides, I hate having to go to the basement to fetch the Milwaukee. I want a dead nuts accurate refractometer on every floor of the house that has a tank.

My tank was a little low on salinity. I knew it was drifting due to wet skimming. Time to test out all 3 salinity probes!

This is dead on:

+.002 as usual (I cover the glass with my hand when it is reading)

Apex is also showing high. Almost as high as my Milwaukee

There it is. Now to see how consistent the Hanna stays over time.

 

[wangspeed]

New feedback already! The Hanna HI98319 is harder to clean off than the Milwaukee. It has lots of books and crannies that should be rinses with RODI and is harder to dry.

My Milwaukee is dead simple, and honestly I usually just use tap water to rinse it off, since our tap is reasonably low in TDS.

 

[Big G]

Thanks for reminding me how much I hate analog refractometers! LOL
Big fan of Hanna's HL Copper Checker and Phosphorous Checker. Another Hanna? Thanks.

 

[marlinmon]

First, let me say this. I hate analog refractometers. My experience is that they go out of calibration if you look at them. Yes you can calibrate each time, but that’s a pain. Also, reading them isn’t exactly clear. Where is the line? It’s fuzzy, so which part of the line do you count as your measurement?

A long time ago, I switched to the Milwaukee MA887. I love it, except for one thing. It is very consistently +.002 SG. It always has been right out of the box. During DC MACNA I spoke to someone at Milwaukee about this and he was super defensive and rude. I found out their calibration standard is different than normal. I got a bottle of it and sure enough, it reads what it says it should. IMO it is -.002 SG from other standards that should be 1.026. I have tried every standard I could get my hands on. It is always +.002.

Strangely, a friend of mine had the Hanna version of this same checker and it is dead on accurate. Maybe Hanna calibrates it with different fluid.

I finally came to the realization that this is fine as long as it is consistent, and it is. It doesn’t lose calibration. Ever. Not a single time that I have tested it has it been off. I’m willing to sacrifice accuracy for this kind of consistency.

Along cake my current tank build with a new 2016 Apex. It has a conductivity probe. Nice! Except everyone complains about it being off. Not mine. Mine doesn’t do wonky things. It reads a little on the high side though.

Just a few weeks ago, I saw the Hanna salinity checker announcement. I guess they retired the old version that is almost identical to Milwaukee. Being a gadget person, I decided to get it. Besides, I hate having to go to the basement to fetch the Milwaukee. I want a dead nuts accurate refractometer on every floor of the house that has a tank.

My tank was a little low on salinity. I knew it was drifting due to wet skimming. Time to test out all 3 salinity probes!

This is dead on:

+.002 as usual (I cover the glass with my hand when it is reading)

Apex is also showing high. Almost as high as my Milwaukee

There it is. Now to see how consistent the Hanna stays over time.

If you cannot see a clear line on your refractometer you've probably got little air bubbles between the lense and lense cover. Even the tiniest pocket of air will cause that line to become fuzzy. Before getting into reefing I used all kinds of refractometers alongside IC for work.

I'd argue the frequency of calibration needed for conductivity type measurements is a lot more than that required of a traditional refractometer.

 

[Gablami]

Almost a year ago, I wasn’t as careful with my salinity and had a few acros rtn on me. Then I got very serious about keeping my salinity stable. I have the Milwaukee, apex probe (which definitely does go wonky on me once in awhile), icecap conductivity probe and my favorite, the pinpoint salinity probe.

I use all of these regularly if you can believe it. My favorite is the pinpoint salinity probe because it doesn’t just give me 1.026 vs 1.027, which is a big margin of error for me. I aim for 52.0 mS and I usually range between 51.5 and 52.5, which is like 1.0251 and 1.255 or something.

Aim small miss small right?

 

[ca1ore]

Your apex shows 34.8 which is essentially 1.025? Why do you say it’s high? What was your reference for the three measurements? My apex salinity goes wonky every now and then; usually because something has fouled the probe.

 

[dwest]

First, let me say this. I hate analog refractometers. My experience is that they go out of calibration if you look at them. Yes you can calibrate each time, but that’s a pain. Also, reading them isn’t exactly clear. Where is the line? It’s fuzzy, so which part of the line do you count as your measurement?

A long time ago, I switched to the Milwaukee MA887. I love it, except for one thing. It is very consistently +.002 SG. It always has been right out of the box. During DC MACNA I spoke to someone at Milwaukee about this and he was super defensive and rude. I found out their calibration standard is different than normal. I got a bottle of it and sure enough, it reads what it says it should. IMO it is -.002 SG from other standards that should be 1.026. I have tried every standard I could get my hands on. It is always +.002.

Strangely, a friend of mine had the Hanna version of this same checker and it is dead on accurate. Maybe Hanna calibrates it with different fluid.

I finally came to the realization that this is fine as long as it is consistent, and it is. It doesn’t lose calibration. Ever. Not a single time that I have tested it has it been off. I’m willing to sacrifice accuracy for this kind of consistency.

Along cake my current tank build with a new 2016 Apex. It has a conductivity probe. Nice! Except everyone complains about it being off. Not mine. Mine doesn’t do wonky things. It reads a little on the high side though.

Just a few weeks ago, I saw the Hanna salinity checker announcement. I guess they retired the old version that is almost identical to Milwaukee. Being a gadget person, I decided to get it. Besides, I hate having to go to the basement to fetch the Milwaukee. I want a dead nuts accurate refractometer on every floor of the house that has a tank.

My tank was a little low on salinity. I knew it was drifting due to wet skimming. Time to test out all 3 salinity probes!

This is dead on:

+.002 as usual (I cover the glass with my hand when it is reading)

Apex is also showing high. Almost as high as my Milwaukee

There it is. Now to see how consistent the Hanna stays over time.

My Milwaukee reads 36 ppt with standards of 35 ppt. Otherwise, I like it a lot. Very consistent and easy to use. I also dislike hand held versions.

 

[wangspeed]

Your apex shows 34.8 which is essentially 1.025? Why do you say it’s high? What was your reference for the three measurements? My apex salinity goes wonky every now and then; usually because something has fouled the probe.

The calculators I checked show 34.8 is 1.026. 33.7 ppt is where it would first start rounding to 1.025.

As far as reference goes, I had just calibrated the Hanna and Milwaukee. There’s no easy way to calibrate the Apex salinity probe. You have to clean it off and let it dry for a day. It has to be bone dry to calibrate it.

 

[Jamie7907]

You don’t have to let it dry for a day. That was a story started by Paul at Neptune so he didn’t have to deal with peoples constant salinity probe issues.

 

[siggy]

During DC MACNA I spoke to someone at Milwaukee about this and he was super defensive and rude

My Milwaukee reads 36 ppt with standards of 35 ppt. Otherwise, I like it a lot. Very consistent and easy to use. I also dislike hand held versions.

I have the same problems. I purchased a defective Milwaukee, took a month to replace and they were very rude. They assured me that I would receive a New unit that was calibrated. Well it reads a point High 1.026 consistently and this drives me nuts so I sent two emails asking for a calibration service and I was willing to pay for it. Never heard back so I just live with it. Wish I bought the Hanna

 

[BestMomEver]

My apex shows ph is about 37. My refractometer shows 1.025. Every time. I have calibrated both. Same thing. I’m trying to ignore the apex display that is facing me all day. It could make an OCD person lose their mind! As I understand, 1.025 should equal about 35. I’m confused with life.

 

[lmm1967]

I have a Milwaukee that is all over the place and I would rate way worse than the silly Neptune probe. And I wouldn't trust the Neptune probe for anything.

I need to make a video to show - you can place a sample - I don't care what the sample is, RO, Calibration solution, tank water, tap water - and the dang thing will show a different measurement every time you press the read button. It's done it since day 1, doesn't matter what temp is, doesn't matter how long you leave the sample in the well etc etc.

And Milwaukee's answer was "clean the sample well". I have a $90 paperweight that is such a point of sale I won't even give it away to someone as I'd hate to see someone think it's any more accurate than tasting your tank water and guessing your salinity that way.

 

[wangspeed]

I have a Milwaukee that is all over the place and I would rate way worse than the silly Neptune probe. And I wouldn't trust the Neptune probe for anything.

I need to make a video to show - you can place a sample - I don't care what the sample is, RO, Calibration solution, tank water, tap water - and the dang thing will show a different measurement every time you press the read button. It's done it since day 1, doesn't matter what temp is, doesn't matter how long you leave the sample in the well etc etc.

And Milwaukee's answer was "clean the sample well". I have a $90 paperweight that is such a point of sale I won't even give it away to someone as I'd hate to see someone think it's any more accurate than tasting your tank water and guessing your salinity that way.

Two things that are important with the Milwaukee. Your sample in the tray has to be completely bubble free. You also should cover the sample area when you hit the read button.

 

[ca1ore]

The calculators I checked show 34.8 is 1.026. 33.7 ppt is where it would first start rounding to 1.025.

That's why I said 'essentially'. Not sure how accurate, or precise, these hobby-grade tools really are. I don't worry too much about accuracy, as long as its within a point or two; I'm much more concerned about precision. So, if the apex reads high, that it always reads high in the same way. My refractometer, for example, always reads my tank at 1.026 versus apex at 36.5-36.8 (which would be almost 1.0128) at 78 degrees. Curious that your refractometer goes out of calibration so often; mine is rock solid. Anyhow, that Hanna look s cool; might have to try one myself.

 

[BestMomEver]

Here you go.... this is what I got this morning....

 

[jsker]

Your sample in the tray has to be completely bubble free. You also should cover the sample area when you hit the read button.

I do the same with the HI 96822 Hanna

 

[lmm1967]

Two things that are important with the Milwaukee. Your sample in the tray has to be completely bubble free. You also should cover the sample area when you hit the read button.

agreed - none of which make a bit of difference on the unit I was sent. Covered, uncovered, bright light, dim light, no bubble, full sample well, not full but fully covering the glass portion of the well.

I can put RO water (or distilled) in the well, let it sit for 10 minutes (they told me to do that to "clean" it), soak it up, wipe gently with micro fiber, add their calibration solution, let sit for 2 minutes, calibrate, wait 30 seconds without touching or changing anything, push test - and 75% of the time it will measure the calibration fluid that was just used to calibrate anywhere from 1.015 to 1.045

And - they were not willing to provide any support even though I purchased it directly from them, via Amazon, and paid $131 for the unit that comes in the protective case etc.

I know plenty of people have good luck with these - but I've also seen several reports similar to my experience.

I now use an American Marine Pinpoint Salinity monitor and as long as I'm sure to not measure in a tank with DC pumps running it seems to stay very accurate. They are sensitive to DC return pumps though.

 

[siggy]

Two things that are important with the Milwaukee. Your sample in the tray has to be completely bubble free. You also should cover the sample area when you hit the read button.

I do the same with the HI 96822 Hanna

Yup I do that over my tank under the light..Still a point high...but like everyone says consistency is key
@jsker I was thinking a Testing and test equip thread or forum needs to be created and can think of no one better than

 

[jsker]

I was thinking a Testing and test equip thread or forum needs to be created and can think of no one better than

I think your on to something.

 

[ca1ore]

My apex shows ph is about 37. My refractometer shows 1.025. Every time. I have calibrated both. Same thing. I’m trying to ignore the apex display that is facing me all day. It could make an OCD person lose their mind! As I understand, 1.025 should equal about 35. I’m confused with life.

BTW, there is an easy way to ‘trick’ the apex into displaying a better number by increasing the temp compensation number. Mine will read 36.8 with no temp compensation, but 35.8 with 2.2.