Alk Spike 7.4-11.4

[jfbhd4]

I did a water change on sat on my 240gal. Put in about 35 gallons of saltwater at around 25ppm. (my salinity was running a bit high on the tank)

Wake up next day and my alk had jumped from 7.4-11.4 and have no clue why. I have a trident system, so tests should be pretty accurate. Did a test on my Hanna and it was around 9.5.

Should i be concerned? I turned my doser off, and it is falling a bit, but has been over 11 for three days now.

 

[Tcook]

Are the reagent bottles on the trident near empty? That volume of water shouldn't have caused such a jump. Did you repeat the Hana test?

 

[jfbhd4]

I have not checked the reagent bottles. I will do that later today. Does being at the bottom of a bottle change the readings?

No i will repeat hana test later also.

 

[Randy Holmes-Farley Verified Community Expert]

I have not checked the reagent bottles. I will do that later today. Does being at the bottom of a bottle change the readings?

No i will repeat hana test later also.

Oddly enough, it seems to cause issues for Hanna and Trident, from what I see folks report.

 

[Gatorpa]

I did a water change on sat on my 240gal. Put in about 35 gallons of saltwater at around 25ppm. (my salinity was running a bit high on the tank)

Wake up next day and my alk had jumped from 7.4-11.4 and have no clue why. I have a trident system, so tests should be pretty accurate. Did a test on my Hanna and it was around 9.5.

Should i be concerned? I turned my doser off, and it is falling a bit, but has been over 11 for three days now.

So let’s talk this through, the trident suddenly jumped 4DkH over night?
Unless you dumped a burping dose of buffer or 2 part it’s unlikely the water change would make that much difference, that leaves a testing error.
You wisely checked it with a Hanna it it still is 2 puts higher than it was. (i’ve found my Hanna) runs about 0.5 dKh higher than my trident.

I would prime the reagents, prime the sample line, check the level of the reagent (on the dashboard).

Did any equipment get moved in the Water change? If so verify there are no kinks and that the sample line is where it should be in the sump..

Retest samples with both instruments and see what you get

 

[bestfishes]

This happened to me when the trident needed to be cleaned. I opened up the unit and used a dry q tip to swab the test chamber and then put it back together. This was approx 7 months after starting up the unit. It may be necessary to do this once or twice a year to keep accuracy.

 

[Nanogeek815]

I tend to see odd readings near the end or beginning of trident reagent bottles.