Kalkwasser not raising alk

[PugsAndFish]

I'm new to the hobby and am going through a few anguishes. For several weeks everything was great until my zoas started closing up and then my euphyllia started looking terrible.

I didn't test my alk everyday because it stayed at a steady 8.6 for a long time so I thought the lack of hard corals wasn't affecting my alk. Then I got algae (which I believe are dinos now). I attributed corals closing to dinos.

Then I decided to test my alk and yikes! A 6.4. Poor coral health is likely due to both dinos and the alk swing. And then my Hanna Alk checker runs out. To salvage, I dripped a bit of kalk into the tank but wasnt able to test how much the kalk was raising my kh.

Anyways I got my Hanna refills today so I tested how much each ml of kalk was doing. I dripped a bit by bit and tested after each ml. I ended up dripping 10 ml but nothing is happening. What's going on?

 

[saltyhog]

What size tank do you have (total system volume if possible)?

 

[PugsAndFish]

What size tank do you have (total system volume if possible)?

10 gallon innovative marine black with a HOB filter

 

[ihavecrabs]

I was always surprised by the sheer amount of fully saturated kalk it took to raise alkalinity in my aquariums (granted mine is slightly larger)

Check out this kalk-ulator to determine the kalk strength and impact on your system.

https://www.hamzasreef.com/Contents/Calculators/KalkContribution.php