high alk readings at exact sametime of day all the time

[SeeFu]

I almost always get these same test results at the sametime of day and was wondering what's causing this issue. Below are just sample test result figures, but they give you the basic idea of what's happening

12am - alk reading of 8
6am - alk reading of 8.5
7:00am - alk reading of 8 (forcing trident to manually test)

I only dose Kwalkwasser at this time, but i always turn off the doser at 5:50am - 6:30am to allow the concentration of kwalkwasser in the sump to settle a bit and get circulated with the display tank. Almost everyday at 6am i get this way higher than anticipated alk reading so i'll test immediately after just to see if i can get a reading that's more inline with what i expect. Attahed photo to show test results. my lights are off at this time so i'm pretty sure its not due to consumption of alk.

The attached photo shows 2 days of testing where the strange reading can be seen. I've dont the retest as early as 6:30am (30 min after the normal tests) and i get the same results. a huge spike at 6am and then back to normal at 6:30am.

I continue to dose kwalk till 12pm (noon) with the same stopping dosing 10 min before and 30 min after the test time, and the noon test results are exactly in line with what i expect it to be as you can see in the chart.

A

 

[dzeleski]

Have you tried moving your sample line to a chamber that is before where your dosing pumps dose?

Make sure your apex and dosing pump software is in sync with time and time zones as well.

 

[SeeFu]

my dosing pumps are DOS so they should all be in sync. The reason i turn off the dosers 10 min before and 30 min after the start of a test is to give the water in the sump a chance to exchange with the display. if you look at my PH, you can tell when its dosing kwalk, there's a huge increase and it takes about 5 min for the PH to return to pre kwalk dosing levels.

my sump is just a 40 gallon breeder w/ no baffles but my UV returns the water back into teh sump to mix everything up.

I just updated my original post to indicate that i continue to dose kwalk until 12pm (noon) and the 12pm trident test gives me a test result that i'm expecting.