iV alk test variability?

[reef altitude]

I have been running my x10/iV for around 7 months now, and wanted to know how consistent results are expected to be.

My results vary from several different salifert test kits by up to .5 dkh (after -1 offset included) and swing wildly 4-5 times a week (8.5, 6 hours later 7.9 and back again to 8.3, manual test is 8.1-8.3 for example).

I have recalibrated the pumps and ph probe regularly, and I clean the probe per pinpoints instructions regularly too. These swings are not consistently months after calibration.

I have tried all the steps in the set up thread as well, to the best of my ability.

Also my ph readings seem more reasonable, so I don't think it is the probe. Even between wildly varying dkh tests the ph is right on pattern (the graph looks about right each day +/- .05 for example).

My tubes are ultra short for reagent, and only a couple of feet to the sump, and I do not see visible bubbles.

Is inconsistent reading +/- .5 dkh expected, and if not what can I do to make this work enough to trust the results?

Thanks for any help!

 

[Michael]

Have you submitted a support ticket? If not please do. Alkalinity is the most violent measurement and can vary quite a bit . Try testing at the same time each day , Once per day. Then you will see what you're consumption rate is . It is not uncommon to see alkalinity swings during the day. If you have more questions please feel free to submit a ticket.

CoralVue Support Portal

support.coralvue.com

 

[BAMatter]

I have the same issue with mine. Everything is calibrated as it should be. I have a feeling that if there was a possibility to narrow the end of the reagent tube that goes into the iV, it will be a more precise reading. @JeffB418 recommended using a plastic dropper and cutting the tip off of it and sliding it into the tube, but I was unable to do that successfully. Wish there was a better way to test this theory out. If you look at the way the Kamoer KHC dispenses reagent, it is precise and uniform, I’m not sure of the Hydros is the same

 

[reef altitude]

Just to update, I replaced the tubing and it ran pretty tight (+/- .1) for 2 weeks. It started drifting up again and I see bubbles in the reagent tube again. I guess I will try the Amazon tubing, hopefully it's thicker/ more elastic and seals stronger on the pump barbs.

 

[Danny]

Just to update, I replaced the tubing and it ran pretty tight (+/- .1) for 2 weeks. It started drifting up again and I see bubbles in the reagent tube again. I guess I will try the Amazon tubing, hopefully it's thicker/ more elastic and seals stronger on the pump barbs.

It could be a reaction to something in the tubing with the reagent. I cleaned my tubing out with tap water and used a syringe to get the water through the tubing rubbing the tubing between my fingers to get out the film in the tubing. I reinstalled it after it dried using an air pump. So far it has bee a couple of months and so far no air bubbles.

 

[Jakerupe]

I have the same simplicity reagent container for my Triton dosing and have found in order to keep the lines free of air bubbles I needed to put o rings over the tubing where they connect to the container. Found the o-rings in a set at home depot but don't have the exact one that had the needed size

**just noticed your line goes straighn into the container