ALK DROPPING BY THE HOUR!!!

[Randy Holmes-Farley Verified Community Expert]

I want to make sure I understand.

Kalkwasser is just limewater, which is saturated calcium hydroxide yes? Dosing it will add alk to the system and also temporarily increase the pH. That increased pH is quite beneficial to coral growth, therefore spurring them to consume more alk in the process.

Surely, though, this process results in a net increase in alk, right?

Yes. :)

 

[Randy Holmes-Farley Verified Community Expert]

I know that. It's just that I was dosing a lot more kalk than I ever have and my ALK was actually dropping in addition to the tank not being too heavily stocked so I was assuming that the kalk was precipitating. I think the answer is that the 50ml of AFR that I stopped dosing was adding a lot more all than I thought it was. My plan moving forward is to adjust the kalk to less than 4,000 ml a day which I am currently at and at the same time go back to AFR with a smaller dosage. I would love to just do one and not the other, but with AFR alone my PH really struggles and with KALK I am not meeting consumption (which to me is the most puzzling). I have seen very heavily stocked SPS tanks running on just Kalk.

It certainly can be that there is substantial precipitation that you do not see. Maybe the pH is already higher than you think.

 

[Adamc13o3]

How can the PH be higher than I think? I have a probe and I test it? If there is precipitation how do I combat it?

Thanks,

Adam

 

[Randy Holmes-Farley Verified Community Expert]

How can the PH be higher than I think? I have a probe and I test it? If there is precipitation how do I combat it?

Thanks,

Adam

By the test being off. I’m not saying it is, but if it was, alk demand and precipitation would be even higher.

 

[Adamc13o3]

PH is lower today and KH increased. So maybe it isn’t precipitating as much? I also noticed that the Kalk is raising the PH as much as it was. Again this is after putting AFR back on. I’m not anywhere as low as I was a few ago, so I guess it’s about fine tuning the two.