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Bob_The_Reefer
09.06.2020, 12:41
I've been running my KHD now for nearly a week and everything is settling down.

Measurements are stable between 10.3 and 10.8 dKH which compares to stable readings on my Hanna Checker between 10.8 and 11.3. Not bothered about the absolute value - just the stability.

Aside from wondering if in fact just moving to the Doser 2.1 was good enough to offer stability versus my previous doser :) I'm now thinking about handing control to the KHD.

My question therefore is:

If with my "KH raising liquid" - in this case Red Sea Foundation B - dosing 1ml raises 0.1 dKH/100l and my tank is 290l net then I need 29ml to raise 1dKH.

Is this then the number that goes into "Volume Change" - 29ml?

I assume that I can then choose a sensible number like 2ml for the "don't add or subtract more than" setting?

Based on the small doses am I better off working with Adaptive Mode or even diluting the alk with 50% RODI and doubling the dosing schedule (bit of a faff)?

Vinny
10.06.2020, 01:33
Yes, that would be one way to do it.

Another way would be to start with a smaller number for value change and see how involved the KHD becomes with adjustments. You can give this one week.
It is up to you which control mode you want to use.

If you would like more information on the differences between Adaptive and Add-on, we have a video which provides that info:

https://www.youtube.com/watch?v=euXBpc0YILs&list=PLZ8mwsVuPz6_4DxuymFqxtnzVxhBgXdCi&index=31

Bob_The_Reefer
10.06.2020, 10:59
Thanks Vinny

When you say "see how involved the KHD becomes with adjustments" how do I get that information out of the doser?

Vinny
10.06.2020, 17:13
If you are controlling through the ProfiLux 4, you will see a history of your dose schedules and where the KHD stepped in and made adjustments.

Bob_The_Reefer
11.06.2020, 10:28
If you are controlling through the ProfiLux 4, you will see a history of your dose schedules and where the KHD stepped in and made adjustments.

I read that as "it is not possible to see dosing history and KHD adjustments using a stand alone doser"

Vinny
12.06.2020, 16:28
Correct.
It will become available in a future update.

Bob_The_Reefer
13.06.2020, 11:49
Correct.
It will become available in a future update.

Thanks Vinny that's good news - allows a gradual switch to GHL - i understand that future updates are difficult to predict but would that by any chance coincide with the ION Director launch?

The Doser 2.1 btw is a solid piece of kit - very impressed, nice simple and intuitive setup.

KHD setup requires a bit of attention to detail but having remeasured the volume of the sample tube and recalibrated the pump the measurements tally with my Hanna checker and Red Sea titration kit within a few tenths of a dKH.

Looking forward to the ION D already

Vinny
15.06.2020, 16:54
Yes, it will be available by the ION launch.