ChaetoGro & Iodine

[Randy Holmes-Farley Verified Community Expert]

Could this explain why with very few corals but lots of chaeto I find my Ca level going down faster than my alkalinity level? Triton should be introducing a balanced input of both so I am scratching my head as I don't understand where the difference is coming from, if not from the macro algae

No, it likely does not. The amount in macroalgae (noncalcifying algae) is not very much, despite the dietary claim of being "rich".


Can you provide more info on what your experience is?

The main reasons for such discrepancies are mismatched dosing pumps, using products not intended for 1:1 dosing, and addition of alkalinity in other ways (tap water, dosing or falling nitrate levels, certain additives, etc.)

 

[Randy Holmes-Farley Verified Community Expert]

So could it be that alk is provided by chaeto?

No, chaeto neither adds nor depletes alkalinity when averages over the course of a day. .

 

[Subsea]

No, chaeto neither adds nor depletes alkalinity when averages over the course of a day. .

considering passive buffering from aragonite substrate and co2 gas solubility contributing to alkalinity with its own dynamic equilibrium constants, it would be difficult to quantify the different dynamics.

 

[Randy Holmes-Farley Verified Community Expert]

considering passive buffering from aragonite substrate and co2 gas solubility contributing to alkalinity with its own dynamic equilibrium constants, it would be difficult to quantify the different dynamics.

CO2 gas does not contribute to alkalinity, regardless of the level. That's somethign that Albert Thiel got grossly incorrect in his books.

Chemistry and the Aquarium: What is Alkalinity?

Randy provides an overview of alkalinity as to why it's important, how it's measured, and how can it be tested.

reefs.com

Alkalinity Facts
There are several facts about total alkalinity that follow directly from the definition. Unfortunately, some of these have been misunderstood by some hobby authors.

One of these facts is termed The Principle of Conservation of Alkalinity by Pankow (“Aquatic Chemistry Concepts”, 1991). He shows mathematically that the total alkalinity of a sample CANNOT be changed by adding or subtracting CO2. Unfortunately, there is an article available on line, which claims otherwise, and encourages people to “lower alkalinity” by adding CO2 in the form of seltzer water. This is simply incorrect.

Forgetting the math for the moment, it is easy to see how this must be the case. If carbonic acid is added to any aqueous sample with a measurable alkalinity, what can happen?

Well, the carbonic acid can release protons by reversing equations 1 and 2:

(5) H2CO3 ==> H+ + HCO3–

(6) HCO3– ==> H+ + CO3—

These protons can go on to reduce alkalinity by combining with something that is in the sample that provides alkalinity (carbonate, bicarbonate, borate, phosphate, etc). However, for every proton that leaves the carbonic acid and reduces alkalinity, a new bicarbonate or carbonate ion is formed that adds to alkalinity, and the net change in total alkalinity is exactly zero. The pH will change, and the speciation of the things contributing to alkalinity will change, but not the total alkalinity.

This is not true for strong acids, however. If you add hydrochloric, sulfuric or phosphoric acids (or any acid with a pKa lower than the carbonic acid endpoint), there will be a reduction in the alkalinity.

 

[Reefr]

No, it likely does not. The amount in macroalgae (noncalcifying algae) is not very much, despite the dietary claim of being "rich".


Can you provide more info on what your experience is?

The main reasons for such discrepancies are mismatched dosing pumps, using products not intended for 1:1 dosing, and addition of alkalinity in other ways (tap water, dosing or falling nitrate levels, certain additives, etc.)

Thank you Randy

What I see is KH staying around 7,7 and even slightly increasing over a week, while Ca would drop by 10 or 12 ppm from 415 ppm. Mg is also not keeping up (loosing around 20 ppm over 2 weeks from 1280 ppm).

I am dosing Triton Core 7, together with Tropic Marin Plus-NP since my P and NO3 are very low (P less than 5 ppb and NO3 0,5 ppm or less). Plus-NP does contain some inorganic nitrates so maybe it could increase alk - but I didn't think this would make a difference (?). How much of an impact can nitrate dosing (or falling) have on alk? Is it possible to quantify?

The daily dose of Core 7 is very small and corresponds to less than 0,1 KH... I have just a few SPS in the tank but based on my experience I expected alk to change more than that. SPS are OK but the tank is still new (4 months) and adjusting.

For feeding I add daily a little of Reef Energy, a little of phytoplankton (easy reefs Easybooster) and zoo replacement (TM's Zooton), plus some enriched frozen mysis for the fish. I also add every week a dose of TM's Nitribiotic.

I recently started doing WC (6 % per week) with ATI natural seawater since my system doesn't seem to be stable with Triton. I do have a little of activated carbon placed in the tank, that I change every 4 weeks.

I dilute Triton Core 7 as I have a nano and I don't think I made a mistake there but I will prepare new solutions this weekend, just to be sure. I have a GHL Doser 2.1 which I recently calibrated and I think it is accurate. I will lower the Triton concentrations so that I can increase the volumes being dosed and hopefully the accuracy.

And I almost forgot but I also dose ChaetoGro daily at the recommended dosage (because of so little Triton Core 7 being added). Chaeto is healthy and growing and I even reduced the lighting time to 8 hours per day (reversed cycle)

 

[Reefr]

I found a post where Randy already answered my question: https://www.reef2reef.com/threads/relationship-between-nitrate-and-alk.354513/post-4400426

 

[Viking_Reefing]

I know that this an old thread but it’s the best I could find discussing iodine in chaeto grow.
I’ve been using it for some time now since I’ve always been chronically low on iron and potassium, figuring that my chaeto sucks it all up.
Iodine has also been fairly low historically.

Well, I’ve been using this stuff for some time now and as I don’t do frequent ICP test I figured that I would way under-dose it and that should be fine.
Some months later I noticed that my clam started opening less and less and when I got RTN on a 20x20 strawberry shortcake colony I figured I broke out one of the tests I had and sent it of.

My iodine is of the charts!

I ransacked my brain to figure out what I’ve been adding that could possibly contain iodine of this magnitude but couldn’t figure it out. The only think I could think of was nori but it’s not like I’m feeding several kilos of it a day.
Since iodine isn’t one of the things listed for this product it didn’t dawn on me before reading up on every supplement I use…dang thing contains iodine.
What’s even more concerning is that my iron is still at zero. I can only deduce that they have made a highly unbalanced product in terms of the actual consumption by macro algae.

Now, I can’t be completely sure of this being the cause but I can’t find anything else that would be…just my two cents.

 

[Randy Holmes-Farley Verified Community Expert]

Iron undetectable may still be far above natural or needed levels that are not detectable by this method.

Maybe you are just using too much.

 

[Viking_Reefing]

Iron undetectable may still be far above natural or needed levels that are not detectable by this method.

Maybe you are just using too much.

Is there a large margins or error in detecting iron using icp-oes that I’m unaware of?
If it was overdosed and brought up my iodine levels to this point I would think that iron would at least be detectable (baring human error in undertaking the test of course).
None of the other elements contained in this product are elevated but rather low as well so I would find it strange if it was a case of a general overdose…but my knowledge might not allow me to draw the right conclusions of the data available.

 

[Randy Holmes-Farley Verified Community Expert]

Is there a large margins or error in detecting iron using icp-oes that I’m unaware of?
If it was overdosed and brought up my iodine levels to this point I would think that iron would at least be detectable (baring human error in undertaking the test of course).
None of the other elements contained in this product are elevated but rather low as well so I would find it strange if it was a case of a general overdose…but my knowledge might not allow me to draw the right conclusions of the data available.

Here’s my comment on iron dosing snd icp from my own test:

Iron (Fe). The natural iron level varies a lot with depth, but surface seawater may have only 0.006 µg/L. The Triton LOD = 0.3 µg/L. I dose iron, and when I dose it I boost iron to roughly 1-2 µg/L, which would be detectable. This sample was taken more than a week after the last iron dosing, and none was detected as it gets depleted in the meanwhile. I’ve not yet seen a Triton test result for a real aquarium sample that had detectable iron, but that doesn’t mean these tanks are necessarily deficient. Iron is also a case where the form is critical, and ICP cannot distinguish form. Binding to organic matter, for example, can alter the bioavailability of iron.

My Triton Testing Results: By Randy Holmes-Farley - REEFEDITION

Recently, Triton GmbH in Germany has initiated a method of testing many ions at once for a single price. In the US, that service is coordinated by Unique Corals. For $49 they will send you a couple of tubes to collect a tank water sample, and a prepaid mailer to send the sample back to them...

www.reefedition.com

 

[Viking_Reefing]

Here’s my comment on iron dosing snd icp from my own test:

Iron (Fe). The natural iron level varies a lot with depth, but surface seawater may have only 0.006 µg/L. The Triton LOD = 0.3 µg/L. I dose iron, and when I dose it I boost iron to roughly 1-2 µg/L, which would be detectable. This sample was taken more than a week after the last iron dosing, and none was detected as it gets depleted in the meanwhile. I’ve not yet seen a Triton test result for a real aquarium sample that had detectable iron, but that doesn’t mean these tanks are necessarily deficient. Iron is also a case where the form is critical, and ICP cannot distinguish form. Binding to organic matter, for example, can alter the bioavailability of iron.

My Triton Testing Results: By Randy Holmes-Farley - REEFEDITION

Recently, Triton GmbH in Germany has initiated a method of testing many ions at once for a single price. In the US, that service is coordinated by Unique Corals. For $49 they will send you a couple of tubes to collect a tank water sample, and a prepaid mailer to send the sample back to them...

www.reefedition.com

Interesting. Thank you!

 

[Randy Holmes-Farley Verified Community Expert]

You're welcome.

Happy reefing.