Bolus dosing

[Welsh Reefer.]

The pH drop on adding bicarbonate, and then the rise as the tank blows off the excess CO2 that the bicarbonate brought in depends on three things:

1. The amount of bicarbonate added.
2. The starting alkalinity.
3. The starting pH.

This graph shows the relationship between alk and pH for seawater that is fully equilibrated with the air around it. Remember that 7 dKH = 2.5 meq/L.

But I don't see a drop? And surely larger the dose the larger the initial drop should be?

Edit - But perhaps the larger spike vs my normal 0.1-0.16 is explained by the lower starting pH?

 

[Randy Holmes-Farley]

But I don't see a drop? And surely larger the dose the larger the initial drop should be?

Edit - But perhaps the larger spike vs my normal 0.1-0.16 is explained by the lower starting pH?

How and where do you dose in relation to where you measure pH?

If a skimmer or other aeration is encountered before you measure pH, you may not see it.

 

[Beruka]

But what conclusions will he be able to draw other than how it compares to the previous method he was using on that specific tank? Which was kalkwasser and a calcium reactor.

Will the conclusions be quantifiable or subjective?

I would trust Reefbum over vendor. He is straightforward and grows colonies easily. I am sure he ran ESV 2 part in past under halides.

Doing A/B studies with recorded growth is for vendor or distributos. Hobbyists have over liflves to live.

 

[Randy Holmes-Farley]

But I don't see a drop? And surely larger the dose the larger the initial drop should be?

Edit - But perhaps the larger spike vs my normal 0.1-0.16 is explained by the lower starting pH?

I’d also suggest a mini experiment if you have time. Take some tank water and add some of your alk supplement to it and see how the pH changes.

 

[Randy Holmes-Farley]

But I don't see a drop? And surely larger the dose the larger the initial drop should be?

Edit - But perhaps the larger spike vs my normal 0.1-0.16 is explained by the lower starting pH?

One final comment on the drop. As I have shown both experimentally and theoretically, the drop is small (0.04 pH units for a 1.4 dKH boost starting at pH 8.1 and 6.3 dKH) ) so that takes relatively little aeration to bring back to no change or be effectively undetectable.

The rise to higher levels (to pH 8.33 for a rise of 0.23 pH units) takes significantly more aeration.

Thus, the fact that you do not readily detect the small pH drop in an operating reef tank is not particularly surprising, and the size of the rise you see is not inconsistent with expectations based on/depending on aeration.

Chemistry And The Aquarium: The Relationship Between Alkalinity And pH

Randy answers many questions in this complex relationship.

reefs.com

I measured to pH change on adding 0.5 meq/L of each of these alkalinity supplements to freshly made salt water (Instant Ocean made to S=35; alkalinity measured to be 2.26 meq/L by titration). Here’s the result for the pH found immediately, and then after 24 and 120 hours of sitting, unstirred, in an open 500- mL beaker:

Supplement	Initial pH	24 hour pH	120 hour pH
none	8.10	8.11	8.21
0.5 meq/L HCO3-	8.06	8.15	8.33
0.5 meq/L CO3–	8.44	8.28	8.34
0.5 meq/L OH-	8.76	8.47	8.33
0.5 meq/L H+	6.91	7.91	8.15

 

[BeanAnimal]

One thing we should all agree, Claud is a brilliant in some aspect.
His product is around for years and he found an elegant way to boost it by slightly changing its dosage (which of course works - as many methods)

No we do not all agree that he is brilliant or that his marketing is elegant.

 

[Welsh Reefer.]

I have just remembered. I did actually do the kitchen bicarb of soda trial back in June, just did not ever get around to writing it up as I'd forgotten to set my KHD to test hourly.

Been back and found the screenshots from the time, it behaved v differently to Fauna KH. Initial pH drop off was observed and very obvious.

Vs today back on Fauna

I guess disclaimers are this was labelled as bicarb of soda from Dr Oetker brand, the wife had used it for baking and I'm unsure if there was any unobvious contamination or any acidic additives etc but there is nothing mentioned on the label. There was also no Trace 3 in the DIY solution as far as I remember.

 

[Big E]

Okay here we go,

1st Feb 2024

August 15th 2024

January 12th 2025 - has been fragged multiple times now.

Thanks, not sure I see anything special in growth or color.

Can you track these two duds I circled........that would be interesting for quarterly updates.

If you're happy that's all that matters, not your job to be Faunas marketing guy:)

 

[Big E]

I would trust Reefbum over vendor. He is straightforward and grows colonies easily. I am sure he ran ESV 2 part in past under halides.

Doing A/B studies with recorded growth is for vendor or distributos. Hobbyists have over liflves to live.

Reefbum is a Fauna accredited advisor for their products.....not sure what that all encompasses. I know for sure it's for the trace elements beyond that I don't know.

I've known Keith for a long time.......kinda disappointed in him for going in this recent direction with his podcasts.

I believe he's been using a calcium reactor and kalk.

 

[Welsh Reefer.]

Thanks, not sure I see anything special in growth or color.

Can you track these two duds I circled........that would be interesting for quarterly updates.

If you're happy that's all that matters, not your job to be Faunas marketing guy:)

In fairness it's hard to spot any special in colour on an all blue colony, but sure, I do tend to keep track of growth on a few of my coral! And no, I'm not a Fauna marketing man so regardless of the wider populations anger or views I'm happy as it's working very nicely indeed for me and my tank :)

 

[Randy Holmes-Farley]

I have just remembered. I did actually do the kitchen bicarb of soda trial back in June, just did not ever get around to writing it up as I'd forgotten to set my KHD to test hourly.

Been back and found the screenshots from the time, it behaved v differently to Fauna KH. Initial pH drop off was observed and very obvious.

Vs today back on Fauna

I guess disclaimers are this was labelled as bicarb of soda from Dr Oetker brand, the wife had used it for baking and I'm unsure if there was any unobvious contamination or any acidic additives etc but there is nothing mentioned on the label. There was also no Trace 3 in the DIY solution as far as I remember.

Curious.

 

[Garf]

There was also no Trace 3 in the DIY solution as far as I remember

You got any of that trace left over?

 

[Welsh Reefer.]

You got any of that trace left over?

Of course.

 

[Garf]

Of course.

Probably nothing, but could you take a pH reading of a capful? Ta

 

[BeanAnimal]

Fauna accredited advisor

:rolling-on-the-floor-laughing:

I i literally spit my coffee out when I read that.

 

[Welsh Reefer.]

Probably nothing, but could you take a pH reading of a capful? Ta

8.6

 

[Oldreefer44]

:rolling-on-the-floor-laughing:

I i literally spit my coffee out when I read that.

The primary role of a FM advisor is to consult on FM ICP results.

 

[BeanAnimal]

The primary role of a FM advisor is to consult on FM ICP results.

That (honestly) sounds even more ridiculous.

 

[Pod_01]

That (honestly) sounds even more ridiculous.

I always wondered what the consultation was about, now I get it.

Send more money, so we can tell you what new bottles to get.

The consultation is completely unbiased and products you choose are up to you, but they will be FM bottles.

 

[Oldreefer44]

Yeah. I don't have a problem with them wanting to be paid for their time but this, to me, comes off as an attempt to ad on some more revenue instead of including it in the price of their ICP test. Especially since you can send your results to Chris Wood at Captiv8 and for $25 he will write a multipage explanation of your results and send a months worth of minor trace element mix based on those results.