"I'm gonna add some Kalk to my ATO to keep pH up" -- How much is needed?

[Rakie]

I always see people say they are gonna add a TINY amount of Kalkwasser to their ATO (or saturated kalk water) and wonder if a "TINY" amount would actually affect pH in the first place.

Imagine you are adding 1 TSP (4.2 grams?) per 5 Gallons. In an SPS dominated tank, say 60+ gallon range, that 1 TSP should have no notable affect on Alk/Cal/Mag, but could that amount actually boost pH? Or is this plan a fools errand without heavily saturated kalk water?

The more I see this, the more I wonder if it's even doing anything at such a low dose.

 

[chipmunkofdoom2]

It depends on the amount added. It will probably boost pH, but not by much.

Increasing the alkalinity by 1.4 dKh with limewater will boost a tank's pH by about 0.6 - 0.7, which is substantial. However, so is a 1.4 dKh boost in alkalinity. In the 60 gallon tank you mention in your post, to boost the alkalinity by 1.4 dKh, this would require 0.7 gallons of fully-saturated limewater. Some tanks evaporate more than this per day, so it is possible to add this much. But, you'll almost never add that much at once, so the pH boost would be smaller throughout the day.

Adding one teaspoon to 5 gallons of water would produce almost no effect on pH. If you dosed the same 0.7 gallons of limewater per day at 1 tsp per 5 gallons, the pH increase would barely be 0.06, and that's over the course of an entire day.

Fully-saturated limewater (2 tsp per gallon) is the best way to go for the maximum pH boost. Alternatively, Randy's new two-part has the exact same pH boost as limewater, but it doesn't have the problem of low solubility, like calcium hydroxide does.

 

[saltyfilmfolks]

When I played with kalk and ph , I added measured amounts of saturated lime water. )mixed settled no grit water only. High 7s and low 8s.

In my 55g (60ish vol w sump)
Wound up settling on 300 ml in my 2.5g ato container to see any improvement in night time early morning ph.
I used about 2.5 gal in just under a week. So 300-500 per week worked for me.

And yes. I agree most don’t use nearly enough.

After a month or so of playing , I stopped the kalk. With a big fuge in reverse and lots of coral my ph never dropped under 8 really , So I quit.
Now my kalk is 5 years old and my ph test is expired and probe is missing.

 

[LouieP]

I always see people say they are gonna add a TINY amount of Kalkwasser to their ATO (or saturated kalk water) and wonder if a "TINY" amount would actually affect pH in the first place.

Imagine you are adding 1 TSP (4.2 grams?) per 5 Gallons. In an SPS dominated tank, say 60+ gallon range, that 1 TSP should have no notable affect on Alk/Cal/Mag, but could that amount actually boost pH? Or is this plan a fools errand without heavily saturated kalk water?

The more I see this, the more I wonder if it's even doing anything at such a low dose.

What is your ph?

 

[Rakie]

Thanks all! This is exactly what I was hoping to hear. This is something I have little knowledge on.

What is your ph?

It averages around 8.1 but this isn't about me or my tank, just looking for general understanding so I could help those I know who want to do something like this. I often also see people thinking that these extremely minor amounts will help a lot, and I wondered how much or little it may impact things.

But who knows... I am switching to a Calcium Reactor, so maybe this information will end up useful to me later.

 

[saltyfilmfolks]

Thanks all! This is exactly what I was hoping to hear. This is something I have little knowledge on.



It averages around 8.1 but this isn't about me or my tank, just looking for general understanding so I could help those I know who want to do something like this. I often also see people thinking that these extremely minor amounts will help a lot, and I wondered how much or little it may impact things.

But who knows... I am switching to a Calcium Reactor, so maybe this information will end up useful to me later.

True.
But your fuge May explode with the co2 , corals too, and compensate.