Anyone seen this 6 in 1 monitor?

[Cell]

Hanna does not like this thread.

 

[cdnco2004]

I trust Hanna more than these honestly. But they work.

 

[Randy Holmes-Farley]

For those rushing into this device falsely claiming to be a 6 in one, you might want to consider the fact that it cannot work correctly for both seawater and freshwater. The interrelationships between sg, conductivity and salinity are different. Which does it use?

If you still want to use it, use only the actual units of measure it actually measures, and not ones it converts with conversions that may not be accurate. Specifically, conductivity in mS/cm or uS/cm, not specific gravity or salinity or TDS..

 

[Randy Holmes-Farley]

I trust Hanna more than these honestly. But they work.

How did you test it to verify it is accurate?

 

[cdnco2004]

SG with a manual refractometer and PH with my Hanna and those are the main things I track.

 

[Randy Holmes-Farley]

SG with a manual refractometer and PH with my Hanna and those are the main things I track.

I would check it with an actual standard before accepting values from it.

 

[cdnco2004]

LIke I said, when I got it I compared it to my Hanna and a Salinity refractometer. Are you saying those are not accurate?

 

[Randy Holmes-Farley]

LIke I said, when I got it I compared it to my Hanna and a Salinity refractometer. Are you saying those are not accurate?

They may or may not be accurate, depending on how you calibrated them, and using a secondary comparison like this doubles the expected uncertainty.

For example, the Hanna salinity meter, even if perfectly calibrated and perfectly used, only claims accuracy to +/- 1 ppt.

if you then use it to "calibrate" a second device with the same uncertainty (not known for the device here), then the uncertainty doubles to about +/- 2 ppt.

Thus, a reading of 35 ppt (sg = 1.0264) could be anything between 33 ppt (sg = 1.0249) and 37 ppt (sg = 1.0279).

A better plan is to make or buy an actual 35 ppt (or other) standard and see what it shows on the device.

 

[cdnco2004]

I did not use a Hana checker for SG as I said, I used a MANUAL Salinity Refractometer.

 

[Randy Holmes-Farley]

I did not use a Hana checker for SG as I said, I used a MANUAL Salinity Refractometer.

That's even more likely to be a problem, IMO.

Which brand and how did you calibrate it?

 

[BanZI29]

I've been using this one since January no issues $70 amazon delivered:

I looked at this one and yea it looks good. however, the biggest attraction of this 6 in 1 is the physical size. Although this one is on ali express and is cheaper!!!!???? yea that irked me a bit. it's made by a different co. thou. this one I bought direct from the maker....I think.

 

[BanZI29]

For those rushing into this device falsely claiming to be a 6 in one, you might want to consider the fact that it cannot work correctly for both seawater and freshwater. The interrelationships between sg, conductivity and salinity are different. Which does it use?

If you still want to use it, use only the actual units of measure it actually measures, and not ones it converts with conversions that may not be accurate. Specifically, conductivity in mS/cm or uS/cm, not specific gravity or salinity or TDS..

Yea I knew that. it truly only shows 3 that are actually useful for us saltys.

 

[Randy Holmes-Farley]

The claimed accuracy is even worse than expected. So bad I doubt they even mean what they write.

In it's measuring range table, it says the accuracy of the reported conductivity is +/- 5% FS, meaning 5% of the full scale.

35 ppt seawater has a conductivity of 53 mS/cm.
The full scale of the conductivity reading is 0-400 mS/cm. Thus the uncertainty is +/- 5% of 400 mS/cm, or +/- a whopping 20 mS/cm. 53 +/- 20 mS/cm? lol

That is so bad it's even hard to believe it is true.

I think I can taste seawater and be more accurate than that. lol

 

[BanZI29]

The claimed accuracy is even worse than expected. So bad I doubt they even mean what they write.

In it's measuring range table, it says the accuracy of the reported conductivity is +/- 5% FS, meaning 5% of the full scale.

35 ppt seawater has a conductivity of 53 mS/cm.
The full scale of the conductivity reading is 0-400 mS/cm. Thus the uncertainty is +/- 5% of 400 mS/cm, or +/- a whopping 20 mS/cm. 53 +/- 20 mS/cm? lol

That is so bad it's even hard to believe it is true.

I think I can taste seawater and be more accurate than that. lol

are you talking about this 6 in 1 or the hanna salinity checker?

 

[Randy Holmes-Farley]

are you talking about this 6 in 1 or the hanna salinity checker?

The 6 in one.

The Hanna salinity claims +/- 1 ppt.

 

[BanZI29]

The 6 in one.

The Hanna salinity claims +/- 1 ppt.

Crap....I hope I didn't just burn $100

 

[Spicy Reef]

The one I use has been dead on in agreement all year with my other test methods, floating hydrometer, refractometer - for PH - hanna PH tester, and red sea.
Just like the name brand, sensors must be kept clean, I've had to wipe them twice and just with my fingers

 

[Randy Holmes-Farley]

sensors must be kept clean, I've had to wipe them twice and just with my fingers

The sensors inside the plastic housing, or the housing itself?

 

[Spicy Reef]

The sensors inside the plastic housing, or the housing itself?

the little glass bubble inside the black "housing"?? not sure if the glass is the housing ur referring to?

 

[LgTas]

Looks like Ill be testing their 30 day no questions return policy