Alkalinity Crash- Need some help!

[DexterPhi]

Hi everyone,
So awhile ago I was struggling with Alk/Calcium, but I was dosing two part when I didn't need to. I came to the conclusion my tank was young enough (less than a year at the time) and didn't have much lps/sps in it so I could probably get away with adding Kalk to my ATO. That worked way better.. My Alkalinity hovered around 8 to the point I got a little lazy about checking it. So last week I checked it and it was close to 5.... I added two part (in two doses) over two day to bring it back to 7 and then increased my kalk dosage in my topoff water to the max on the bag (BRS says 2 teaspoons per gallon).

Well it just so happened that my ATO screwed up after my weekly water change (I'm still not sure how) and put about an extra gallon of water in the tank (total tank volume is 30 gallon). The whole tank clouded up with a bunch of precipitant on the glass that was surprisingly tough to get off. The PH spiked to 8.7... I noticed about an hour later, dosed 20 ml of white vinegar and then did a 33% water change... Everything in the tank seemed grumpy but has slowly bounced back (except strangely for my "weeds" xenia is limp and green star polyps look are still not coming out)

That was 3 days ago... So I just checked today and my PH is 8.34, but my alkalinty is at 5 again....

I wondered if I had a bad test, but I checked twice and got 5.2 and 5.4 both times. I also checked a little pico tank I literally just setup over the weekend with all brand new water and no coral yet and it came in at 8.2).....

FWIW my ATO uses about a half gallon per day so bascially I'm adding a teaspoon of kalk per day...

What should I do now??????

 

[Backreefing]

Does your ATO have a optical sensor? If so makeing a surround for may help . Often light can make it unreliable. I would do a water change .

 

[DexterPhi]

Yep it does. It hadn’t been a problem in the past, but I’ll try that... I just don’t understand how I can go from an overdose of kalk to 5 in 3 days.....

 

[Backreefing]

To much kalk can cause a precipitation event . Raining carbonate . . I never had it happen. But whenever in doubt = water change . It fixes everything

 

[NitrateKillah]

Check MAG. its OFF.

 

[Doctorgori]

unrelated but Make sure the Kalk isn’t fogging up/coating that Optical sensors
...strongly endorse checking Mag in tandem

 

[Randy Holmes-Farley Verified Community Expert]

Hi everyone,
So awhile ago I was struggling with Alk/Calcium, but I was dosing two part when I didn't need to. I came to the conclusion my tank was young enough (less than a year at the time) and didn't have much lps/sps in it so I could probably get away with adding Kalk to my ATO. That worked way better.. My Alkalinity hovered around 8 to the point I got a little lazy about checking it. So last week I checked it and it was close to 5.... I added two part (in two doses) over two day to bring it back to 7 and then increased my kalk dosage in my topoff water to the max on the bag (BRS says 2 teaspoons per gallon).

Well it just so happened that my ATO screwed up after my weekly water change (I'm still not sure how) and put about an extra gallon of water in the tank (total tank volume is 30 gallon). The whole tank clouded up with a bunch of precipitant on the glass that was surprisingly tough to get off. The PH spiked to 8.7... I noticed about an hour later, dosed 20 ml of white vinegar and then did a 33% water change... Everything in the tank seemed grumpy but has slowly bounced back (except strangely for my "weeds" xenia is limp and green star polyps look are still not coming out)

That was 3 days ago... So I just checked today and my PH is 8.34, but my alkalinty is at 5 again....

I wondered if I had a bad test, but I checked twice and got 5.2 and 5.4 both times. I also checked a little pico tank I literally just setup over the weekend with all brand new water and no coral yet and it came in at 8.2).....

FWIW my ATO uses about a half gallon per day so bascially I'm adding a teaspoon of kalk per day...

What should I do now??????

The precipitation event caused by the addition of excessive limewater (kalkwasser) causes a big drop in alk that can actually drive the alk much lower than it was before the event.

That is because all of the fresh calcium carbonate surfaces act as seed crystals for more precipitation, potentially dropping the alkalinity to the levels you see.

There is nothing unusual and no reason to suspect any other issues (such as low magnesium) are driving the processes (although magnesium might coincidentally be low).

You need to wait a few days before redosing to allow all of those surfaces to become coated with organics, phosphate, and magnesium, all of which will block further precipitation.

I'd restart dosing in about 3 days, and start slowly without the kalkwasser for now to keep the pH lower (also reducing precipitation).

Then slowly ramp back up.