Trident Alkalinity Readings See-Saw

[cshouston]

I’ve been running my trident for over a week now, and it has been through the calibration process. Still, my alkalinity readings see-saw every other reading from high to low and back again.

this really illustrates the effect I am seeing. I have the trident running 8 tests per day. One is higher, one is lower, then higher, then lower. What could be causing this weird pattern and is there a way to fix it? I don’t expect every test to be exactly the same result, but this bouncing back and forth can’t be working as intended.

 

[SuncrestReef]

Are you using Trident Controlled Dosing? See my Trident thread to see how I smoothed out the swings:

Trident - Hands on

I received my Trident today and set it up. For full details, see this post in my build thread: https://www.reef2reef.com/threads/suncrestreefs-red-sea-reefer-xl-425-build.358990/page-31#post-6036364 Here's a photo of the inside mechanics of the Trident. I haven't seen this posted anywhere...

www.reef2reef.com

 

[cshouston]

No, I’m not. I haven’t installed the DOS yet. This is just straight up testing. I only hand dosed once which is that first big spike, but the swinging occurred before and after.

 

[Brett S]

It is kind of interesting to see that, but it’s also worth noting that the variation you are seeing is less than .2 dkh, which is really very small. Because your alkalinity and the readings are so consistent the graph magnifies those tiny changes and they look much bigger than they are.

As far as what’s causing it, the only thing that I can imagine is that it’s related to the calcium and magnesium tests. The trident will test just alkalinity for one cycle, then it will test alkalinity, calcium, and magnesium on the next cycle. I suspect (and this is just a guess) that there is either a tiny amount of something left over from the magnesium test that affects the next alkalinity test, or after the alkalinity only test the residue left affects the next alkalinity test.

But in any case, like I said, the variation is really tiny in the grand scheme of things and I really wouldn’t worry about it.

 

[Brett S]

Just for fun, I took a look at my graph and I’m seeing a similar effect. I’m only testing 4 times a day, so my graph is a bit more spread out than yours, but there still seems to be a see-saw effect between readings.

 

[cshouston]

Interesting. There must be something throwing it off during the multiple tests. Neptune advertise the trident as being accurate to within .05dkh so .2 dKH swings are not in spec, regardless. I’ll give them a call and see what they have to say.

 

[Thales]

Alk is not stable, it fluctuates. I wouldn't blink at a .2 wiggle

 

[infinite0180]

Imho you really cant expect it to be better than that. Thats really stable...

 

[Brett S]

Alk is not stable, it fluctuates. I wouldn't blink at a .2 wiggle

I agree that it’s nothing to be concerned about, but I do think that it’s interesting that it’s changing so consistently, moving up and then down by the same amount with each test.

 

[cshouston]

Right, it’s not that I expect it to be rock stable (though I also don’t dose yet because my consumption is really low), it’s just the pattern of differences between alk only tests and combined tests. Something isn’t quite right with the machine to be throwing a .2 difference every single time.

 

[cshouston]

Anyway, I have a ticket open with Neptune so we’ll see what they say once they look at my apex and get back to me.

 

[hart24601]

I have noticed the exact same which I was talking about with my friend before he found this thread. It must have something to do with the alternating alk vs alk/ca/mg. I upped the testing to 8x a day and the oscillation stayed the same. I use all for reef so it’s not a timing issue with dosing. It’s not a big deal however it is odd.

 

[hart24601]

Alk is not stable, it fluctuates. I wouldn't blink at a .2 wiggle

I don’t think we are concerned with the swing, just the mechanism or process inside the trident that is giving these alternating values for curiosity sake as this would indicate the actual alk is either not accurate on the combined test or the true value is between the two values. I suspect the combined test alk value is slightly off. Not that it it is causing concern.

 

[hart24601]

Looking at my graph the lower alk numbers do match up with the combined testing at even when changing sampling frequency so it will be interesting to hear what Neptune says.

 

[cshouston]

Looking at my graph the lower alk numbers do match up with the combined testing at even when changing sampling frequency so it will be interesting to hear what Neptune says.

Interesting that you have the exact same issue. I’ll update this thread after I get done with Neptune support!

 

[uninformed]

Was there ever a resolution with Neptune?

 

[ReefKeeperElite]

My Trident does the exact same thing. More curious than anything, but just wondering what Neptune has said to explain the alk dips when combined tests are performed. I will open another ticket with them if nobody has gotten any feedback.

 

[codytrandall]

Im seeing the same issue, did anyone get a response from Neptune?

 

[Rob181]

I believe it can possibly be because of the consumption rates of the tank. Depending on when you dose too. How often are you dosing?

 

[hart24601]

I believe it can possibly be because of the consumption rates of the tank. Depending on when you dose too. How often are you dosing?

At least for me that isn’t the case as if you fun two back to back there is no yo-yo, it seems, for mine, to be related to the combined test and the alk alone. Fwiw I dose kalk every 15 min but off set so it doesn’t overlap with trident test and even if did have a huge powerhead in sump.