Salinity probes...what's the story here? Why aren't they reliable?

[Lbrdsoxfan]

I agree. I have had great results with the Hanna meter but my Apex salinity probe is all over the place.

Have you heard of the SPS? It's a salinity probe stability kit. It sends water through it constantly eliminating bubbles, etc. I have one on hand and plan on installing it this weekend. I will update afterwards. Seems promising though.

Salinity Probe Stability Kit (SPS)

Monitoring salinity in an aquarium can be a challenge-- small bubbles and debris can interfere with your conductivity probe, leading to inconsistent and unreliable results.Vivid Creative Aquatics has tackled this problem head on with their Salinity Probe Stability Kit. The "SPS" Kit is carefully...

www.bulkreefsupply.com

I did a diy version of the sps kit. Imho it works pretty well. Keeps me in a .2-3ppt swing throughout the day.

I just use some silicone hose connected to a 50gph pump.

 

[Rich Klein]

I've tried them all and hands-down I love the Hanna wand. Not sure why some on this string have not shared the same experience (HW defect?)? I calibrate it about once a month, and use it for every water change - matching the newly mixed water with the tank water regardless of the value. If the tank salinity needs to be adjusted (rarely) I do it slowly over the week.

 

[elcapitan1993]

I will echo the dislike of the Hanna Salinity Checker. It drifts a lot and very quickly in my experience.
I prefer the digital refractometers.

@eag Has a fantastic thread on the Apex salinity probe stability here:

(Almost) Everything You Need to Know About Apex Salinity Calibration and TC Factor

I was trying to calibrate my new salinity probe a few weeks ago, and ran into all sorts of problems. Calibrations that were way off the mark, big fluctuations in readings that couldn't possibly be correct (and were verifiably not), etc. After searching around the internet, it was clear that a...

www.reef2reef.com

I have this Hanna salinity pen and I love it, it’s the best one I could find, I used the Milwaukee one for over a year and it was horrible, probably the worst one that is being sold honestly, I get much more reliable and consistent results using the Hanna pen, you just have to make sure you actually calibrate it once a month like it says in the user manual, I’m surprised to hear 2 people say they don’t like it

 

[neonreef3d]

get this,,,, game over!!!

High Precision Hydrometer

Ensure that your equipment is reading correctly and your aquarium is at the right salinity with Tropic Marin's High Precision Hydrometer. Many tank inhabitants are sensitive even to minor changes of the water conditions. Unfortunately as we've all experienced, salinity reading equipment as...

www.bulkreefsupply.com

 

[elcapitan1993]

I've tried them all and hands-down I love the Hanna wand. Not sure why some on this string have not shared the same experience (HW defect?)? I calibrate it about once a month, and use it for every water change - matching the newly mixed water with the tank water regardless of the value. If the tank salinity needs to be adjusted (rarely) I do it slowly over the week.

I agree it’s the best one I could find and it’s so reliable, I think the problem is most people aren’t calibrating it once a month like they should be, I calibrate mine exactly at the 30 day mark and NEVER had a problem, it also seems to
Me you calibrate it like you should and you also have no issues with it.

 

[elcapitan1993]

get this,,,, game over!!!

High Precision Hydrometer

Ensure that your equipment is reading correctly and your aquarium is at the right salinity with Tropic Marin's High Precision Hydrometer. Many tank inhabitants are sensitive even to minor changes of the water conditions. Unfortunately as we've all experienced, salinity reading equipment as...

www.bulkreefsupply.com

I heard these are SUPER inaccurate

 

[Leisuretron]

They all suck and I finally went old school and got a hydrometer that floats. This helps me compensate for the crappy meters, because I have a known baseline to work from.

Which hydrometer are you using? I’m new to reefing and like the sound of having something old school that works and is not electronic for spot checks.

 

[iamahab]

I will echo the dislike of the Hanna Salinity Checker. It drifts a lot and very quickly in my experience.
I prefer the digital refractometers.

@eag Has a fantastic thread on the Apex salinity probe stability here:

(Almost) Everything You Need to Know About Apex Salinity Calibration and TC Factor

I was trying to calibrate my new salinity probe a few weeks ago, and ran into all sorts of problems. Calibrations that were way off the mark, big fluctuations in readings that couldn't possibly be correct (and were verifiably not), etc. After searching around the internet, it was clear that a...

www.reef2reef.com

The one I have worked well for about a month and then went sideways on me. By the time I got a different meter (pinpoint) I was calibrating it before every use. I still didn't trust it then. The pinpoint meter works well for me and is far more stable

 

[iamahab]

I heard these are SUPER inaccurate

They're super big

 

[HuduVudu]

Which hydrometer are you using? I’m new to reefing and like the sound of having something old school that works and is not electronic for spot checks.

High Precision Hydrometer

Ensure that your equipment is reading correctly and your aquarium is at the right salinity with Tropic Marin's High Precision Hydrometer. Many tank inhabitants are sensitive even to minor changes of the water conditions. Unfortunately as we've all experienced, salinity reading equipment as...

www.bulkreefsupply.com

You need something that will allow the hydrometer to float without being disturbed. This also needs to be something that you can see from the side.

This will always give you the correct reading and it doesn't drift. The downside is that it is glass.

Hope this helps.

 

[Ntvper]

Please forgive my ignorance but I don’t see why it matters. Hear me out I’m all for providing the best for my pets but equipment fails or puts out a false reading based on factors that’s I’m not totaling aware of but cleaning and consistently doing the same thing with the same measurements of salt and temp I get to the point where I don’t care what the equipment says as long as it’s stable. I use the apex probes and Hanna probes/testers to give me an idea where everything is at. But due to my schedule and maintenance I’m not constantly seeing big swings in the salinity range. My equipment keeps the tank in the 77 range tops out at 77.9 and the salinity seems to swing from 32.7 - 33 inside the temp range as well. This is my first apex and I will agree I know nothing of it but again I haven’t seen or ran across any of those issues that everyone is speaking of. My curiosity is why it matters if we do the same measurements and same routines then salinity and temp should never be an issue right? I’m so lost

 

[Randy Holmes-Farley]

Please forgive my ignorance but I don’t see why it matters. Hear me out I’m all for providing the best for my pets but equipment fails or puts out a false reading based on factors that’s I’m not totaling aware of but cleaning and consistently doing the same thing with the same measurements of salt and temp I get to the point where I don’t care what the equipment says as long as it’s stable. I use the apex probes and Hanna probes/testers to give me an idea where everything is at. But due to my schedule and maintenance I’m not constantly seeing big swings in the salinity range. My equipment keeps the tank in the 77 range tops out at 77.9 and the salinity seems to swing from 32.7 - 33 inside the temp range as well. This is my first apex and I will agree I know nothing of it but again I haven’t seen or ran across any of those issues that everyone is speaking of. My curiosity is why it matters if we do the same measurements and same routines then salinity and temp should never be an issue right? I’m so lost

It is a mistake to assume that the only issues for devices are simply being off by the same fixed amount every time.

Many people report issues that appear to be fluctuations in parameters of all sorts that are not likely fluctuating but are actually test problems.

That said, I do agree that reef aquaria organisms are fairly nondemanding of a specific salinity, and there's a fairly wide range of acceptable salinity that allows reefers to be successful with a wide range of salinity measuring devices.

 

[Ntvper]

It is a mistake to assume that the only issues for devices are simply being off by the same fixed amount every time.

Many people report issues that appear to be fluctuations in parameters of all sorts that are not likely fluctuating but are actually test problems.

That said, I do agree that reef aquaria organisms are fairly nondemanding of a specific salinity, and there's a fairly wide range of acceptable salinity that allows reefers to be successful with a wide range of salinity measuring devices.

Ty, but forgive me what’s the mistake or factor that plays in a device that’s off by the same fixed amount? I understand equipment ‘trails’ off but again if your measuring using the same method what’s the issue? That’s assuming your following the manufactures recommendations. I am trying to learn here I swear I always feel like I’m missing something that’s big enough to cause my pets stress. And trying to prevent that it’s worth any effort. I’m no expert but I have fish from fifteen and ten years obviously not the same tank

 

[Randy Holmes-Farley]

Ty, but forgive me what’s the mistake or factor that plays in a device that’s off by the same fixed amount? I understand equipment ‘trails’ off but again if your measuring using the same method what’s the issue? That’s assuming your following the manufactures recommendations. I am trying to learn here I swear I always feel like I’m missing something that’s big enough to cause my pets stress. And trying to prevent that it’s worth any effort. I’m no expert but I have fish from fifteen and ten years obviously not the same tank

The problem is in assuming that devices do not drift or otherwise change from your assumption of being off by a fixed, unchanging amount.

Let's look at a random example, the first one I found on googling:

" wanted to ask on here if any one has been having issues with Hanna's Salinity checker HI98319. It was working like a champ for the first couple of months with regular calibrations every month. Now it is not staying calibrated to save its life! I have used a few other checks (refractometer, Hanna refractometer) and those are consistent. The deviation between just a few day is .05 Specific gravity depending on the day, basically rendering this thing useless unless I wanted to calibrated it everyday"

HANNA Salinity Checker Issues

Hi All, I wanted to ask on here if any one has been having issues with Hanna's Salinity checker HI98319. It was working like a champ for the first couple of months with regular calibrations every month. Now it is not staying calibrated to save its life! I have used a few other checks...

www.reef2reef.com

 

[KStatefan]

I heard these are SUPER inaccurate

Where did you hear that? People that have posted experiences with them on reef2reef have been positive. I mixed up some of Randy's calibration fluid when I got mine and it checked right.

 

[Fredrxn]

My apex probe has been dead on for months since I Calibrate it with tank water

 

[Garf]

My apex probe has been dead on for months since I Calibrate it with tank water

Bit like the folks that calibrate their seneye ammonia doodad, with tank water, to hell with convention, and science, lol

 

[Sean Clark]

I have this Hanna salinity pen and I love it, it’s the best one I could find, I used the Milwaukee one for over a year and it was horrible, probably the worst one that is being sold honestly, I get much more reliable and consistent results using the Hanna pen, you just have to make sure you actually calibrate it once a month like it says in the user manual, I’m surprised to hear 2 people say they don’t like it

I am glad to hear that you are having a better experience with you Hanna Salinity Tester than I have had. Perhaps I just had a bad unit. There are lots of reports of others having the same issues even with proper calibration.
I have never used the Milwaukee refractometer, so I won't try to add anything to that.
I use the Hanna HI96822 Seawater Refractometer and love it.

The one I have worked well for about a month and then went sideways on me. By the time I got a different meter (pinpoint) I was calibrating it before every use. I still didn't trust it then. The pinpoint meter works well for me and is far more stable

This is very similar to what I experienced. It still works as a thermometer, but that is all I would trust it for.

 

[Ntvper]

So I think we can agree that everything varies and we should assume nothing……

 

[Randy Holmes-Farley]

So I think we can agree that everything varies and we should assume nothing……

When it is something out of your control, then it's a matter of trust. So much of reefing is.

Do you trust that manufacturer "A" put the right chemicals in its salt/additive/etc. Checking is way to expensive.

Do you trust that even the standard you are using is accurate? Depends on the company, IMO. Hobby companies are always suspect until they somehow demonstrate and earn our confidence. Big science supply and food supply companies are much less suspect.

A bottle of Morton's food grade sodium chloride or Mrs Wages pickling lime or an Oakton conductivity standard or 0.1 N HCl from Fisher Scientific is highly unlikely to be substantially off, but is every ingredient in a commercial two part or salt mix actually added correctly?