Alk is going up
 

Last week I noticed my alkalinity was high, it was nearly 15.5 dkh. Took my mall stirrer offline and straight ro water for tip-off. Been testing daily ever since, started to see a decline. Monday it was 13.05 dkh. Tested this morning when I got home from work and it has gone up, now reading 13.45 dkh. Why would this go up if I am not dosing to the tank? My nitrates are around 2-5 (salifert test and my eyes can’t tell which one it is, phosphates are .1 calcium is 475. Mag is 1320. Some corals don’t seem affected while others have no PE.

So questions are

1 why has the alk suddenly gone up?
2 best way to get it down?

Thanks in advance

mall stirrer?

I do not believe that its possible for alk levels to rise in a tank without the addition of an alk supplement or performing water changes with a higher ratio..
It may just be in test kit inaccuracy..

Its possible that your dosage (I assume kalk through the ATO) was inconsistent too causing a rise..

Kalk stirrer, freaking autocorrect on phone and I didn’t catch it sorry. Haven’t done a water change in a week and using a Hannah meter. Tested it 5 times this morning with very little change in readings like less than .1 difference between them

Kalk stirrer has been offline for 9 days as of now.

You're not adding any "buffer," are you? That raises alk.

No, nothing added since I noticed it high

That change is fairly small. I'm not sure what's happening, but there might be some testing limitations in play. I would give the tank a few days to see how it's going to respond.

Not much change in alk. Has gone down 2 ppm in 2 days. My concern is that it is 238 ppm which is 13.3 dkh which is high. I know letting it go down naturallly over time is best but at this point with the decrease at the current rate it will be like 3 weeks before it is in a normal range. Thoughts?

13.3 dKH should be safe enough for quite a while. I would ignore it, personally.