How much kalk should I start with?

[zachfishman]

I'll soon be starting a kalk dosing regimen for my 29, I figure that switching from CaCl dosing to kalk will lessen the severity of my nightly pH swings (8.1 - 7.8). I know I should first raise my Ca to a desired level and then adjust the amount of kalk to maintain consumption, but how much should I be starting with?

The Reef Chemistry Calculator is a great tool for calculating how much saturated limewater will raise my DT volume by X ppm of Ca, but:

1. How much kalk per liter/gal makes it saturated? (I won't have a former reactor and was thinking of dosing diluted kalk)
2. How much will my DT pH rise when I add X amount of kalk?

 

[HighlandReefer]

Kalk water is saturated at around 2 teaspoons per gallon.

Kalk water is best dripped to maintain pH and in your situation wanting to prevent pH lows at night it would be best to drip your required amount of kalk water over the night period.

In most cases it is recommended to start with 1 teaspoon of kalk per gallon and make adjustments from there.

Adding 1.25% of the total tank volume with sautrated kalk water will boost pH by an unacceptable 0.6 to 0.7 pH units.

 

[HighlandReefer]

FWIW, adding 0.4% of your total tank water using saturated kalk water, will raise your pH around the maximum amount you want to increase your tank pH (0.2). So if you have a 100 gallon total water volume system, you would not want to add more than 0.4 gallons of saturated kalk water to this size system at one time. More than this can cause damage to your tank occupants. One needs to be careful to have proper checks and balances to prevent kalk water overdose.

 

[tozzi]

U can make it easy by just adding the kalk to your top off water if you have an ato. This way it gets added in small doses through the day

 

[Porcupinepuffer]

I've seen my tanks ph go from 8.2 - 8.5 within the 10 minutes it takes my kalk reactor to finish from when the ATO stops. So if I'm reading this correctly, I'm adding way too much kalk in relation to what is acceptable? All my inhabitants are fine btw.

 

[HighlandReefer]

It is usually not recommended to allow your pH rise more than 0.2 pH units. That said, a little more may not hurt as you have described for your situation. I would not let your pH rise above 8.5 though. I would say you are pushing it though.