10.27 dKH and 373 Ca. How is that possible?

[FrostyKevin]

Got an ATI ICP test done. And my dKH is 10.27 while my Ca is 373. I dose only All 4 reef. Coralline algae is spreading all over my tank, which I think is tanking my Ca, but it's not doing anything to my dKh. What's going on? Also, I have a fishless system.

Screenshot of ICP test:

 

[MnFish1]

What are the tests that you measure at home. You should be able to measure calcium and alkalinity. If your results are 'in range' - I would ignore ICP since ICP only uses a test (like yours) to measure alkalinity)

 

[Randy Holmes-Farley Verified Community Expert]

what salt mix are you using?

A number of things can move alk up or down without changing calcium

 

[FrostyKevin]

What are the tests that you measure at home. You should be able to measure calcium and alkalinity. If your results are 'in range' - I would ignore ICP since ICP only uses a test (like yours) to measure alkalinity)

I'm using Hanna, which also confirms the same trend (low Ca and high Alk)

 

[FrostyKevin]

what salt mix are you using?

A number of things can move alk up or down without changing calcium

I'm using Brightwell Salt.

 

[MnFish1]

I'm using Brightwell Salt.

Did you happen to mix the bucket I.e. tip it up and over several times - second - did you let it mix 24 hours before using?

 

[FrostyKevin]

Did you happen to mix the bucket I.e. tip it up and over several times - second - did you let it mix 24 hours before using?

Yes, I never change the water or add newly mixed water. I wait a few days.

 

[MnFish1]

Yes, I never change the water or add newly mixed water. I wait a few days.

Sorry - I'm not sure I was clear - did you mix the bucket the salt was in up down across, etc - multiple times before mixing?

 

[FrostyKevin]

Sorry - I'm not sure I was clear - did you mix the bucket the salt was in up down across, etc - multiple times before mixing?

Oh ok, no I haven't tbh. I didn't think of it.

 

[Randy Holmes-Farley Verified Community Expert]

I'm using Brightwell Salt.

Do you have alk and calcium test kits to try?