Alk changes throughout the day

[BAMatter]

For simplicity’s sake take a 100 system mixed reef with 1ml/min kalk being dosed… how often, how much is a reasonable amount to see for a difference in alk over the course of 3 hours? I’m trouble shooting an auto tester, and getting some readings that are a bit, I don’t know, abnormal (to me) but may be legit.

9.18dkh
3 hours later 9.02dkh
3 hours later 9.13dkh

Are these possible numbers with consistent alk drip?

 

[Ron Reefman]

Try only testing once or twice a day and then compare them with tests at the same time the next day.

 

[jda]

I doubt that you have a test kit that is accurate enough to really get a sense of what is happening at such a granular level. Most test kits are going to be .1 or .2 of error range.

I also would test once a day at about the same time and look at the trend more than the absolute numbers.

With kalk, pH is more of a thing than small changes in the dKh.

 

[fishyjoes]

There's a good kalkwasser calculator at https://www.hamzasreef.com/Contents/Calculators/KalkContribution.php

You can use this to see how much calcium and alkalinity a certain amount of kalk should have on your system. I've found it to be pretty accurate

 

[Randy Holmes-Farley Verified Community Expert]

Those numbers look perfectly reasonable and are hardly changing at all.

 

[BAMatter]

Those numbers look perfectly reasonable and are hardly changing at all.

Ok, that’s what I was looking for. I’ve never had an automated alk tester so I’ve only tested via a Hannah checker typically once a day, twice at very most if I was dialing in 2 part, so I never knew how it fluctuates during the day, or what was considered a large variance in a few hours timespan.