Hanna vs Trident | Wildly different ALK readings...

[BetterJake]

Recently got a trident, working well and calibrated correctly.

ALK is coming in consistently around 6.8. Hanna Alk checker is reading 8.3.

1.5 is a pretty big difference, I'm not sure which to trust. Could the hanna alk reagent be bad? I'm fine dealing with the usual margin of error but this big of a difference it's hard for me to gauge is I should dose or not.

 

[Jimbobalou622]

How old is the reagent?

 

[BetterJake]

How old is the reagent?

It's been open for a few months, bottle has an expiration of 05/24

 

[Jimbobalou622]

It's been open for a few months, bottle has an expiration of 05/24

Any mishandling that you know of?

 

[Stevorino]

Let me preface this with saying that I love Trident and have used it for years

Trident readings should never be taken as 100% reliable. I do think that generally the trends you see using the Trident are very representative of what is going on in the tank.

I still check my Alkalinity on average once a week using a Hanna checker. Sometimes after calibrating the Trident I will re-calibrate it with tank water using the Hanna's results.

All this is to say, I wholeheartedly trust Hanna more 10 times out of 10, but still find significant value in Trident in the form of watching day-to-day trends so that I can dial in my dosing.

 

[BetterJake]

Let me preface this with saying that I love Trident and have used it for years

Trident readings should never be taken as 100% reliable. I do think that generally the trends you see using the Trident are very representative of what is going on in the tank.

I still check my Alkalinity on average once a week using a Hanna checker. Sometimes after calibrating the Trident I will re-calibrate it with tank water using the Hanna's results.

All this is to say, I wholeheartedly trust Hanna more 10 times out of 10, but still find significant value in Trident in the form of watching day-to-day trends so that I can dial in my dosing.

100% consistency and the trend is what I care about at the end of the day.

It's just knowing when to start tracking that trend, if that makes sense. If I go on trident I need to bump up my ALK 1.5 and then track the trend and maintain or via Hanna dose nothing right now and then maintain.

 

[braaap]

I calibrate with tank water. Test the 3 parameters and then average them out. Put those in for your calibration and calibrate.

I also use ABC regents and find them far more reliable.

 

[Charlie the Reefer]

I routinely test alk with hanna, trident, and ICP.

When I do my monthly ICP I measure my Alk/cal/mag with my trident and Alk with Hanna immediately after taking the sample for ICP.

It could just be my case, but consistently Trident is generally .1-.2 dkh below Alk indicated on ICP, whereas Hanna is generally a full ~2 dkh high.

So… I shoot for trend as others have suggested, but I do trust my trident more.

 

[flatlander93]

I would never trust Hanna 100%. Iv had major issues with consistency of mine. Salifert For the win! I use one of those little magnetic stirrers when I add the drops and it works great. Easier for me than a Hannah.

 

[Stevorino]

100% consistency and the trend is what I care about at the end of the day.

It's just knowing when to start tracking that trend, if that makes sense. If I go on trident I need to bump up my ALK 1.5 and then track the trend and maintain or via Hanna dose nothing right now and then maintain.

I always start with Hanna.

I personally calibrate Trident with their calibration fluid... and after it's done calibrating, I cross-check to Hanna. If it's the same, good stuff. If it's different, then I re-calibrate the unit to Hanna.

 

[Reefer Matt]

I made a video for this too, but I’ll just leave this here.

https://www.neptunesystems.com/getstarted/trident/calibration/

 

[BetterJake]

Well I just tested freshsly mixed water with the Hanna. Should have tested at 8 and came in at 9.3. So seems Hanna is testing about 1.3 higher

 

[Oldreefer44]

Hanna always came in about 1.2 higher than Trident. Very important that needles are straight down into reagent bottle. Hanna was always very close to ICP results. I agree with others that Trident is most valuable for monitoring trends versus exact numbers.

 

[gbroadbridge]

Recently got a trident, working well and calibrated correctly.

ALK is coming in consistently around 6.8. Hanna Alk checker is reading 8.3.

1.5 is a pretty big difference, I'm not sure which to trust. Could the hanna alk reagent be bad? I'm fine dealing with the usual margin of error but this big of a difference it's hard for me to gauge is I should dose or not.

Hanna Alk reagent lasts about 1-2 months after opening. It lasts to the expiry unopened.
You can make it last longer by refrigerating after opening - then it'll last 6 months or so.

Try some fresh reagent if the difference bothers you.

I use Salifert Alk as a standard test as it is very stable and reliable.