Different alk results

[aerialdronemaster]

Hello
Guys, I need help
I tested alkalinity in the tabk , it's 8.2

Tested in the ato( where return pomp is ) 7.9

Tested with hanna checker.

No , calibrated trident that is taking sample from ato show 6.88

Wt....f

Want to add. Weeks before, before adding corals and fish i added a lot of alkalinity, magnesium and calcium to bring levels up. It caused precipitation, maybe it is dissolving in the tank now ? And slowly goes to the sump ?

By the trident?

 

[Randy Holmes-Farley Verified Community Expert]

Those two values are well within Hanna's claimed uncertainty for the device of +/- 0.3 dKH.

Unless you are adding something between the two locations (like fresh water top off), the values are almost certainly the same.

Just assume your alk is 8 dKH.

 

[arking_mark]

When you say ATO, you mean sump, right?

I'm using a GHL KH Director to measure my Alk, and Hanna to double check. My observations have been that Hanna and GHL almost always match between 7.3 and 8.6 readings. Outside that range the Hanna seems to not match and stays way closer to the 7.3 and 8.6 range.

So I personally trust the GHL more than the Hanna.