Red Sea Alk kit issues

jtlmnop · Feb 21, 2021

I have been using the Red Sea all kit and for a while was getting the expected results, around 8dkh. Recently I have been seeing a drop in alk using the 5ml titration. I have added a few soft corals, so maybe that was expected.

I did a 25% water change on my 50gal tank, mixing Instant Ocean at 1.026 in RO/DI, and was getting values around 4dkh on multiple tests. I tried the 10ml titration and got a result of 10dkh on multiple tests.

how could there be that big of a difference between to two titrations, and which so I believe?

I am thinking about getting the Hanna Alk tester, but I still don’t understand why this would happen.

Any thoughts?

Spare time · Feb 21, 2021

Are you saying that when you used 10ml sample water you got 10KH and 4KH in 5ml sample water? If so, you are supposed to use 10ml, and which in that case it would make sense that half the water use would resulting roughly half the kH reading.

jtlmnop · Feb 21, 2021

Spare time said:
Are you saying that when you used 10ml sample water you got 10KH and 4KH in 5ml sample water? If so, you are supposed to use 10ml, and which in that case it would make sense that half the water use would resulting roughly half the kH reading.

Thanks, that makes sense. I think I was just interpreting the instructions wrong...