DIY Balling Method needs extra alk?

[jackintheboxfish]

For DIY balling method of 1:1:1 Calcium Chloride, Soda Ash, and Balling Part C, does soda ash needs to be a little more?

My understanding is that for coral skeleton, 1:1 ratio of Ca and Alk makes sense, but there will be other organisms that consume Alk (algae, bacteria, etc.) so to ensure calcium doesn’t creep up over time if I dose according to Alk, should I dose a little more Soda Ash compared to CaCl2?

 

[Randy Holmes-Farley Verified Community Expert]

For DIY balling method of 1:1:1 Calcium Chloride, Soda Ash, and Balling Part C, does soda ash needs to be a little more?

My understanding is that for coral skeleton, 1:1 ratio of Ca and Alk makes sense, but there will be other organisms that consume Alk (algae, bacteria, etc.) so to ensure calcium doesn’t creep up over time if I dose according to Alk, should I dose a little more Soda Ash compared to CaCl2?

With a few exceptions, those organisms do not consume alkalinity.

In fact, most organisms consuming alkalinity, such as coralline algae or some macro algae such as halimeda, only do so because they are depositing calcium carbonate.

There are some processes that add or consume small amounts of alkalinity:
1. Accumulating nitrate depletes alkalinity.
2. Falling nitrate, or nitrate dosing and consumption adds alkalinity
3. Sulfur denitrators deplete alkalinity.
4. Ammonia chloride dosing depletes alkalinity.

Most folks find 1:1 is pretty close, and deviations may be more related to dosing pump issues or recipe measurement issues that a demand ratio way off of about 2.8 dKH for each 18-20 ppm of calcium consumed.

This has more:

When Do Calcium and Alkalinity Demand Not Exactly Balance? by Randy Holmes-Farley

 

[jackintheboxfish]

Hey Randy! Thanks for the explanation. I didn’t know that other consumers of alk are most likely making Ca2CO3 like corals do even though some of them are macroalgae that don’t seem have a skeleton or shell.

I remember reading somewhere that you dose AFR for your tank and add in alk if needed. I might’ve remembered wrong but if that’s the case, do you do it because AFR doesn’t have the exact 1:1 in terms of ca and alk?

 

[Randy Holmes-Farley Verified Community Expert]

Hey Randy! Thanks for the explanation. I didn’t know that other consumers of alk are most likely making Ca2CO3 like corals do even though some of them are macroalgae that don’t seem have a skeleton or shell.

I remember reading somewhere that you dose AFR for your tank and add in alk if needed. I might’ve remembered wrong but if that’s the case, do you do it because AFR doesn’t have the exact 1:1 in terms of ca and alk?

Macroalgae without skeletons do not (cannot) consume alkalinity. There is nowhere for it to go.

I dose AFR and do not need any other alk. But, AFar is slightly overbalanced to extra calcium. It has the exact ratio as in calcium carbonate, like kalkwasser does, but real skeleton formation and abiotic precipitation has some magnesium getting into the skeleton in place of an equal number of calcium ions, and hence the calcium demand is actually a little
Bit less than one guesses from pure calcium carbonate.

Pure calcium carbonate is 2.8 dKH per 20 ppm calcium.

Real consumption is about 2.8 dKH for 18-20 ppm calcium and about 1 -2 ppm magnesium.