Which dKH test should I believe?

[ScottF]

I just replaced the reagent bottles in my Trident and ran a calibration. I broke out all of the test kits because I wanted to verify that it was calibrated correctly. I don't know which test to believe for alk. I did all three tests multiple times and they are consistent with themselves, but the results of each test are wildly different from each other.

dKH
Trident 8.53 and 8.54 (two tests)
Hanna Alk checker 10.1 and 10.2 (three tests. 10.1 twice)
Salifert 10.9 (two tests. 10.9 twice)


Calcium
Trident and Salifert matched EXACTLY at 424

Mag
Trident and Salifert matched EXACTLY at 1420

 

[ScottF]

Hanna reagent bottle was dated 5/2025. Salifert test kits were all dated 2029. There appears to be a lot number on the bottom of the Trident reagent bottles, but I don't see a date.

 

[gbroadbridge]

I just replaced the reagent bottles in my Trident and ran a calibration. I broke out all of the test kits because I wanted to verify that it was calibrated correctly. I don't know which test to believe for alk. I did all three tests multiple times and they are consistent with themselves, but the results of each test are wildly different from each other.

dKH
Trident 8.53 and 8.54 (two tests)
Hanna Alk checker 10.1 and 10.2 (three tests. 10.1 twice)
Salifert 10.9 (two tests. 10.9 twice)


Calcium
Trident and Salifert matched EXACTLY at 424

Mag
Trident and Salifert matched EXACTLY at 1420

The Hanna and the Salifert are so close it doesn't matter so I'd believe those.

It's likely you are going too far into the pink with Salifert (the endpoint is purple).

 

[Kooma]

The Hanna and the Salifert are so close it doesn't matter so I'd believe those.

It's likely you are going too far into the pink with Salifert (the endpoint is purple).

That’s good info. It indicates more of a solid change instead of the mid color change such as purple.

 

[gbroadbridge]

That’s good info. It indicates more of a solid change instead of the mid color change such as purple.

General consensus is that if you go to full pink you've gone about 1-2 drops too far if you want an absolute number. Doesn't matter of course if you just want a consistent number for tracking

The accuracy of both tests is about +/- 0.3 dkh so if you split the difference you'll be pretty much around 10.5.

 

[ScottF]

I just cracked open another bottle of calibration fluid. This time I tested some with the Hanna checker before I inserted the tubing from the Trident. The bottle says the calibration fluid is 8.7. The Hanna checker agreed that it's 8.7.

I'm now calibrating the Trident again. If it still doesn't match, I'll test what is left from the calibration fluid in the Hanna checker to see if I'm tainting the fluid when I insert the line.

 

[Troylee]

I just cracked open another bottle of calibration fluid. This time I tested some with the Hanna checker before I inserted the tubing from the Trident. The bottle says the calibration fluid is 8.7. The Hanna checker agreed that it's 8.7.

I'm now calibrating the Trident again. If it still doesn't match, I'll test what is left from the calibration fluid in the Hanna checker to see if I'm tainting the fluid when I insert the line.

Use the Hannah to test your tank water. Once you got a number calibrate the trident off the Hannah reading and be done.. it works perfectly.

 

[ScottF]

Use the Hannah to test your tank water. Once you got a number calibrate the trident off the Hannah reading and be done.. it works perfectly.

That's pretty brilliant. Use the calibration fluid that comes with the Trident reagents to verify the Hannah checkers and then use the Hannah checkers to get the water parameters. Then calibrate using the tank water.

Don't have to worry about contaminating the sample, matching the bottle to the water line or any of that nonsense.

 

[Cichlid Dad]

I just replaced the reagent bottles in my Trident and ran a calibration. I broke out all of the test kits because I wanted to verify that it was calibrated correctly. I don't know which test to believe for alk. I did all three tests multiple times and they are consistent with themselves, but the results of each test are wildly different from each other.

dKH
Trident 8.53 and 8.54 (two tests)
Hanna Alk checker 10.1 and 10.2 (three tests. 10.1 twice)
Salifert 10.9 (two tests. 10.9 twice)


Calcium
Trident and Salifert matched EXACTLY at 424

Mag
Trident and Salifert matched EXACTLY at 1420

Are you adding reagent in the Salufert until it turns fully blue or just until it grays

 

[ScottF]

Are you adding reagent in the Salufert until it turns fully blue or just until it grays

I think I was doing fully blue.. I did verify the Hanna checker with the Trident calibration solution. It was spot on with what was on the calibration solution bottle. So I'm choosing to believe the Hanna is giving me the correct results.

After doing the calibration again using the solution, it is still reading 8.5 dKH instead of 10. I am now trying to do the calibration using tank water and using the reading from the Hanna as the calibration target.

I am in the middle of switching from All for Reef to Kalkwasser + 2 part and it would be super helpful if I could get somewhat reliable readings from the Trident while I get everything stabilized again.

 

[ScottF]

After calibrating with tank water to a target of 10 and running an Alk test, it finally came back with 10.08. Hopefully it stays somewhat accurate.

 

[Troylee]

That's pretty brilliant. Use the calibration fluid that comes with the Trident reagents to verify the Hannah checkers and then use the Hannah checkers to get the water parameters. Then calibrate using the tank water.

Don't have to worry about contaminating the sample, matching the bottle to the water line or any of that nonsense.

I don’t bother with the sample water from Neptune… I know Hannah is solid so I just test my tank water with the Hannah for alk , salifert for calcium and mag and use that number to calibrate my trident! The trident works extremely well at holding the alk calibration steady but it likes to drift on calcium and mag over time..

 

[ScottF]

I don’t bother with the sample water from Neptune… I know Hannah is solid so I just test my tank water with the Hannah for alk , salifert for calcium and mag and use that number to calibrate my trident! The trident works extremely well at holding the alk calibration steady but it likes to drift on calcium and mag over time..

This is what I'll probably do in the future as well. I just figured I could use the water from Neptune maybe once a year or once every six months to make sure the Hanna doesn't drift. I tested two different calibration bottles from Neptune with the Hanna and both were spot on. I was surprised that it matched the label exactly.

 

[ScottF]

So my (less than 6 month old) Trident just won't hold calibration. It was reading low again the next day. As of 10 minutes ago:

Hanna: 9.9 dKH
Trident: 8.3 dKH

Salifert: 450 CA
Trident: 312 CA

I opened a ticket with Neptune Support. I'll wait and see what they come up with.

 

[ScottF]

So my (less than 6 month old) Trident just won't hold calibration. It was reading low again the next day. As of 10 minutes ago:

Hanna: 9.9 dKH
Trident: 8.3 dKH

Salifert: 450 CA
Trident: 312 CA

I opened a ticket with Neptune Support. I'll wait and see what they come up with.

After lots of back and forth between me and Neptune support, I figured out today that there was a partial clog in the tube between the manifold and the sample line.

I had to disconnect the tube from the manifold and solenoid. Then I used some water in a metal tip syringe from a box of Franks F Aiptasia to blow out the clog.

Hopefully this fixes my issue.