Calcium dropping much faster than alkalinity when using kalkwasser

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The two part is designed to maintain all the major ions (sodium, calcium, magnesium, chloride, and sulfate). Trace elements may rise due to impurities, or may fall. Minor elements (such as potassium) will depend on their concentration in the two part ingredients, but some will likely decline. In my DIY it was maintained (see above data in link). A good commercial two part will not have any of the important major, minor or trace elements changing.
 
WWC
Discontinued water changes and kalk dosing, it's still doing it. Remixed two part according to your recipe using kents turbo calcium (anhydrous calcium chloride) and arm&hammer baking soda. It's still doing it. Double checked my dosing pumps to make sure they were operating at the same rate. They are.

I have another theory now. When I was mixing up the two part I noticed I was able to add a lot more baking soda into a 1 cup measuring cup by compressing/flattening the powder with my hand. This leads me to believe that there will be a significant difference in actual grams of the substance added depending on what form it comes in and how you measure assuming you measure by volume (which most reefers do). So I bought an accurate 1KG scale and calibrated it with a 500g weight. The next batch of two part I will make by using weight measurement instead of volume for the CaCl2 and NaHCO3 which should be more accurate.

The other potential issue might be that the turbocalcium may not be pure anhydrous calcium chloride which could through my concentration off. It does seem to make a significant amount of precipitate in the bottle that has to settle out, even when mixed to a much lower concentration than its max solubility point.

I also noticed that a thick calcium carbonate crust is forming on the glass of my refugium. It is clearly abiotic as it has no coloration. I have no idea why it's forming there and nowhere else.

I've also noticed that I'm able to maintain more stable levels with significantly less solution added when using the dosing pumps instead of manual dosing. Which leads me to believe that a significant portion of the loss can be attributed to abiotic precipitation due to high local concentrations of two part not having fully diffused throughout the tank. Despite the low concentrations of solution I use and powerful circulation pumps in the sump where I dose.

It's a shame so many people hate calcium reactors. They seem to be the best system for maintaining good levels in high demand tanks without affecting salinity or trace element levels.
 
FWIW, Kent Turbo Calcium (anhydrous calcium chloride) CANNOT be substituted into my recipe (using calcium chloriode dihydrate) without reducing the amount because it is not an equivalent chemical to Dowflake. Did you adjust for that?

The fluffiness (bulk density) of solids will impact how much you are using if you measure by volume. The recipe may need to be adjusted if you are not using the exact materials I specified, even if they are chemically the same.

That cannot be an issue with limewater, however, since alk and calcium are tied together.
 
Nutramar Foods
Adam Obenauf said:
It's a shame so many people hate calcium reactors. They seem to be the best system for maintaining good levels in high demand tanks without affecting salinity or trace element levels.
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Relative to limewater (kalkwasser), they will actually add less calcium per unit of alkalinity delivered, so wouldn't be a "solution" to apparent excess calcium demand.
 
Randy Holmes-Farley said:
FWIW, Kent Turbo Calcium (anhydrous calcium chloride) CANNOT be substituted into my recipe (using calcium chloriode dihydrate) without reducing the amount because it is not an equivalent chemical to Dowflake. Did you adjust for that?
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Yes. The article said to use 20% less so I did.

Randy Holmes-Farley said:
That cannot be an issue with limewater, however, since alk and calcium are tied together.
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Yup. Right now I'm thinking the issue was caused entirely by the two part dosing. I would need to switch to limewater only for awhile to confirm this which I cannot due without my levels quickly dropping way too low.

Randy Holmes-Farley said:
Relative to limewater (kalkwasser), they will actually add less calcium per unit of alkalinity delivered, so wouldn't be a "solution" to apparent excess calcium demand.
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I thought both were perfectly balanced?

At 300ml per day of each solution (25ml every 2 hours, even hours for calcium, odd hours for alkalinity) I observed a drop of about 10ppm of calcium per day and a rise of about 0.2 dKH of alkalinity per day. So I have adjusted calcium to 360ml per day to try to offset the apparent imbalance. I will check my readings after a week to see if it worked and report back.
 
Limewater is balanced exactly to calcium carbonate.

But in a reef tank, magnesium and strontium get incorporated in place of some of the calcium. So it overdelivers a little too much calcium, and folks using it (like me) find the calcium rises higher than the new salt water over time.

If the effect you are seeing is from a DIY two part, there are many possible reasons for that, and just dosing more of the calcium part is a fine correction. :)
 
www.dinkinsaquaticgardens.com
So far it seems to be working. Day 4 and alk/ca are still balanced.

I still don't see how it's possible to have other elements at correct NSW levels using two part unless you're using a salt mix that has everything except chloride and sulfate (since those are being added but not consumed) massively elevated to do water changes. Say I do a 6.66% water change every week with 1.0215 SG saltwater to keep my salinity from rising due to two part dosing. If that saltwater mixes potassium (just to use as an example) to NSW levels at 1.0265 which is pretty standard than my potassium levels (and every other ion we don't measure) will be massively depleted no matter what I do. Unless I discontinue two part dosing and start using regular salinity again for my water changes or dose trace elements and just hope that they end up at the right levels.
 
Adam Obenauf said:
So far it seems to be working. Day 4 and alk/ca are still balanced.

I still don't see how it's possible to have other elements at correct NSW levels using two part unless you're using a salt mix that has everything except chloride and sulfate (since those are being added but not consumed) massively elevated to do water changes. Say I do a 6.66% water change every week with 1.0215 SG saltwater to keep my salinity from rising due to two part dosing. If that saltwater mixes potassium (just to use as an example) to NSW levels at 1.0265 which is pretty standard than my potassium levels (and every other ion we don't measure) will be massively depleted no matter what I do. Unless I discontinue two part dosing and start using regular salinity again for my water changes or dose trace elements and just hope that they end up at the right levels.
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Are you asking how it is possible? It does work out chemically that all a two part does (if perfectly designed) is to boost calcium and alkalinity, and raise salinity with all other elements in the proper ratio. They are all added with a product like B-ionic. Water changes aren't the best way to reduce salinity, although it can work if you use reduced salinity added. You can just remove a small amount of tank water and replace it with fresh. Skimming wet may already do this. :)
 
I think you might be misunderstanding my question? To add calcium or carbonate with two part (which are consumed by biotic/abiotic precipitation) you have to also add sodium/chloride (which are not consumed). Those build up over time raising the salinity. The only way to combat that is to drop the salinity which reduces levels for all other ions. How is it possible for this to not be the case (for other elements to not drop over time with two part)? Water changes of course could help but in order to stay balanced in a high demand system every ion except chloride/sulfate would have to have massively inflated levels (potassium for example) to combat this dilution effect. And testing on these salt mixes shows that isn't the case, they generally target NSW levels for major ions.
 
Adam Obenauf said:
I think you might be misunderstanding my question? To add calcium or carbonate with two part (which are consumed by biotic/abiotic precipitation) you have to also add sodium/chloride (which are not consumed). Those build up over time raising the salinity. The only way to combat that is to drop the salinity which reduces levels for all other ions. How is it possible for this to not be the case (for other elements to not drop over time with two part)? Water changes of course could help but in order to stay balanced in a high demand system every ion except chloride/sulfate would have to have massively inflated levels (potassium for example) to combat this dilution effect. And testing on these salt mixes shows that isn't the case, they generally target NSW levels for major ions.
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Yes, I understand that question.

A two part like B-ionic ADDS all the other ions too (potassium, sulfate, bromide, strontium, etc.). So that when you drop salinity, there is no net depletion of anything relative to natural seawater..
 
My original DIY two part, which is not as perfect as commercial versions, maintains the major ions (sodium, chloride, potassium, magnesium, calcium, sulfate) but depending on the purity of the materials, may not add enough of some of the minor ions. For trace elements, it may add more or less than needed to maintain exact NSW.

I show how that is calculated here:

http://reefkeeping.com/issues/2006-02/rhf/index.php
 
So those potassium impurities actually keep it stable, interesting. What about bromine and fluorine? Those are present at high levels in seawater too and I would think they would be important.
 
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So I recalibrated my dosing pumps the other day and the alk pump is running 20% faster than the Ca pump. Which explains why I had to dose 20% more Ca to stay balanced. 4 days since then dosing the same amount of both and the levels are still stable. That was the issue all along.
 
Adam Obenauf said:
So I recalibrated my dosing pumps the other day and the alk pump is running 20% faster than the Ca pump. Which explains why I had to dose 20% more Ca to stay balanced. 4 days since then dosing the same amount of both and the levels are still stable. That was the issue all along.
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Sounds good!

Happy Reefing. :)
 
Randy Holmes-Farley said:
The effect you are seeing is definitely not from the limewater (kalkwasser).

If you are actively using organic carbon dosing or growing macroalgae to reduce nitrate levels that are high, that can also raise alk and not calcium.

What salt mix are you using?
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Do you mean more alkalinity will be used with macro algae? Or more calcium?

Wish I knew how to erase posts. Nevermind, I see you've already responded to this question.
 
Top Shelf Aquatics
jduong916 said:
Do you mean more alkalinity will be used with macro algae? Or more calcium?

Wish I knew how to erase posts. Nevermind, I see you've already responded to this question.
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No problem. Happy Reefing [emoji3]
 

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