Dosing kh and Calcium

[6lue9uy]

My tank have been running for just one year. And recently I noticed my kh started to dropping alot faster.
I was dosing about 10ml sodash fr brs for the past half year keeping it at around 8.8-9.
But started this month my kh started to drop 0.2 each day after 20ml dosing.

As for my Calcium I am planning to add another doser but from what I see currently. My Calcium drop 10ppm every 2 day ish, I am manually adding 100ml to keep it at 360ppm for the past week. (Trying to bring it up to 380 current testing how much I need to add)

Just wondering if that's normal. It's a 40 breeder with 30g sump. With all lps frags. The mag level been hovering around at 1200 no dosing

 

[ReefRusty]

When was the last time it was been calibrated? Have you manually tested to confirm some similarities in drop?

 

[6lue9uy]

When was the last time it was been calibrated? Have you manually tested to confirm some similarities in drop?

Last calibration was beginning of the month, and only tested kh right after with hanna checker to confirm the results. Have not yet manually tested anything since, will do it tomorrow to check the results.