BRS soda ash to Kalkwasser ratio

[dirtie]

Currently using BRS soda ash as part of the 2 part dosing. Thinking of switching to saturated Kalkwasser, but can't find out how much I'd need to dose. Need to know the ratio, so Xml of soda ash equates to Xml of kalk to match dkh consumption?

 

[GillMeister]

My understanding is kalk doses both Ca and alk in the right proportion. I don't think you need to dose soda ash unless the kalk dosing isnt keeping up.

 

[Randy Holmes-Farley Verified Community Expert]

My DIY two part Recipe #1 (used by BRS) is exactly 46.5 times as potent as saturated limewater (kalkwasser) at 25 deg C in terms of alkalinity delivered.

This calculator can be used for such calculations:

Reef Chemistry Calculator

 

[Pntbll687]

Ok
Step 1 - go here, https://reef.diesyst.com/chemcalc/chemcalc.html

Step 2 - Enter system volume
Step 3 - enter your alk consumption for the day (you should already know this since your dosing two part). You can use whatever numbers you want, just as the difference between the two is how much your alk consumption is. Example - your alk drops .3 over 24hrs right now, Use 7.0 as current alk and 7.3 as desired alk.
Step 4 - select "saturated limewater" as additive
Step 5 - This will give you the TOTAL DOSAGE. Spread this dose out over the day.

Note - I would start at 75% of the dosage recommended to account for any over estimate of water volume on your part

 

[Pntbll687]

Since @Randy Holmes-Farley said above, his 2 part recipe is used by BRS, and is 46.5 times as potent, this means you would multiple what your dose is now by 46.5 to get the saturated kalkwasser dosage

 

[dirtie]

My DIY two part Recipe #1 (used by BRS) is exactly 46.5 times as potent as saturated limewater (kalkwasser) at 25 deg C in terms of alkalinity delivered.

This calculator can be used for such calculations:

Reef Chemistry Calculator

Thanks for the reply Randy. This was what I was looking for to see how much volume I would need for a reasonable container size. I'm assuming the Randy's recipe 1 is soda ash and recipe 2 is sodium bicarbonate.

 

[thatmanMIKEson]

Ok
Step 1 - go here, https://reef.diesyst.com/chemcalc/chemcalc.html

Step 2 - Enter system volume
Step 3 - enter your alk consumption for the day (you should already know this since your dosing two part). You can use whatever numbers you want, just as the difference between the two is how much your alk consumption is. Example - your alk drops .3 over 24hrs right now, Use 7.0 as current alk and 7.3 as desired alk.
Step 4 - select "saturated limewater" as additive
Step 5 - This will give you the TOTAL DOSAGE. Spread this dose out over the day.

Note - I would start at 75% of the dosage recommended to account for any over estimate of water volume on your part

I like the steps and makes sense im going to try this

 

[Randy Holmes-Farley Verified Community Expert]

Thanks for the reply Randy. This was what I was looking for to see how much volume I would need for a reasonable container size. I'm assuming the Randy's recipe 1 is soda ash and recipe 2 is sodium bicarbonate.

Yes.

http://reefkeeping.com/issues/2006-02/rhf/index.php

 

[SilentSloth]

My DIY two part Recipe #1 (used by BRS) is exactly 46.5 times as potent as saturated limewater (kalkwasser) at 25 deg C in terms of alkalinity delivered.

This calculator can be used for such calculations:

Reef Chemistry Calculator

Is there a way to know how much soda ash will effect my PH assuming I know my starting point or is that not possible to calculate?
Is there a time period between Kalk and Soda Ash I should wait so they don't potentially form a precipitate?

 

[Randy Holmes-Farley Verified Community Expert]

Is there a way to know how much soda ash will effect my PH assuming I know my starting point or is that not possible to calculate?
Is there a time period between Kalk and Soda Ash I should wait so they don't potentially form a precipitate?

The instantaneous rise is about 0.35 pH units for each 1.4 dKH added (it varies with the starting point and the total alk present).

When added over time the rise is much lower as the tank pulls in CO2 to offset the rise. That part cannot be calculated.

 

[SilentSloth]

The instantaneous rise is about 0.35 pH units for each 1.4 dKH added (it varies with the starting point and the total alk present).

When added over time the rise is much lower as the tank pulls in CO2 to offset the rise. That part cannot be calculated.

Thanks! Couldn't find that info anywhere, and I really didn't want to learn the chemistry to do the math myself.

 

[Randy Holmes-Farley Verified Community Expert]

Thanks! Couldn't find that info anywhere, and I really didn't want to learn the chemistry to do the math myself.

Its something that I measured and reported here:

Chemistry And The Aquarium: The Relationship Between Alkalinity And pH ? Advanced Aquarist | Aquarist Magazine and Blog