Bolus dosing

[Randy Holmes-Farley]

Back on the hypothesized mechanism for any perceived benefit, I'll focus on this comment from the document I posted:

Using Fauna Marin Balling Light carbonate, it is possible to raise the pH substantially just before the start of the photoperiod by dosing the entire daily requirement in one dose, this is the Bolus. The timing is very important as there is a chemical re-balancing that can take between 10-30 minutes, this should be the delay between the Bolus dose and the start of the photoperiod.

and this picture:

Clearly, several things jump out.

1. As someone noted earlier, FM calls their product used here Fauna Marin Balling Light carbonate. It raises pH which is also consistent wit it being wholly or partly carbonate, not just bicarbonate. Bicarbonate will not raise the pH like that (yes, I have tried it).

2. FM claims the pH boost is important.

3. It is very plausible, IMO, that the pH is important. Most of us believe that many hard corals grow faster at higher pH, and if that growth mostly happens during the lit hours, then the higher pH during those hours immediately following the bolus dose may explain wholly or partly the improvements folks see.

4. If #3 is the explanation, then other means of attaining that pH may accomplish the same goals, without bolus dosing.

 

[Randy Holmes-Farley]

Can someone explain what the chemical phenomenon is?

"The Bolus method creates a chemical phenomenon where the amount of alkalinity measured on a
test kit will be misleading in the first hours of the bolus dose."

An advertising fantasy, in this situation. There is no such thing if one doses bicarbonate, carbonate, or hydroxide. All of those are instantly and completely detected by alkalinity titration.

If you dose an organic alk form (such as the formate in AFR or acetate in Salifert all in one), then one needs to wait for it to be metabolized to be detected.

 

[DutchReefer420]

OK, let's start again.

How much alk do you dose once each day, and when does it decline after dosing?

Also for @Garf

I can document this all for you guys if you need me to!!
of course there are slight variations on every test we do due to accuracy

If you need me to, i will show you what time i dose and how much! also i can show you al the measurments with time and date

to verify, alk test kit is brand new (salifert)

my alk is 7.5DKH

every morning 30 min before the lights come on i dose 260ML of alk this should be around 2.5dkh.
When i measure alk 60min after the dose it will read 7.5 dkh.

The most decline ive seen was at 30 min before the next dose ''early morning'' and the ALK was 7.2 DKH.
'this was because i was dosing not enough!!

So i then put this 0.3 DKH decline in my calculator and add the extra amount of alk to my bolus dose for that morning.

I dont know what the alk will be directly after dosing because i only took a measerment 60min after dosing.

I never stated that my ALK will NEVER drop, also i dont know the scientific reason why this is happing
I can only show you my dose and measurments

 

[Garf]

Also for @Garf

I can document this all for you guys if you need me to!!
of course there are slight variations on every test we do due to accuracy

If you need me to, i will show you what time i dose and how much! also i can show you al the measurments with time and date

to verify, alk test kit is brand new (salifert)

my alk is 7.5DKH

every morning 30 min before the lights come on i dose 260ML of alk this should be around 2.5dkh.
When i measure alk 60min after the dose it will read 7.5 dkh.

The most decline ive seen was at 30 min before the next dose ''early morning'' and the ALK was 7.2 DKH.
'this was because i was dosing not enough!!

So i then put this 0.3 DKH decline in my calculator and add the extra amount of alk to my bolus dose for that morning.

I dont know what the alk will be directly after dosing because i only took a measerment 60min after dosing.

I never stated that my ALK will NEVER drop, also i dont know the scientific reason why this is happing
I can only show you my dose and measurments

You got a pic of the tank?

 

[elysics]

Can anyone explain in detail (experimental or even just theory) the data rationale suggesting timing is important?

As I understand it, without having tried it, the idea is to strike a balance between photosynthesis starting early and driving up pH and growth, and the overdose of bicarb shifting the equilibrium between bicarb, carbonate and carbonic acid to a point where rather than alkalinity being used up, alkalinity stays fixed while the accumulated carbonic acid that was formed after dosing converts back and is used up instead

 

[Randy Holmes-Farley]

Also for @Garf

I can document this all for you guys if you need me to!!
of course there are slight variations on every test we do due to accuracy

If you need me to, i will show you what time i dose and how much! also i can show you al the measurments with time and date

to verify, alk test kit is brand new (salifert)

my alk is 7.5DKH

every morning 30 min before the lights come on i dose 260ML of alk this should be around 2.5dkh.
When i measure alk 60min after the dose it will read 7.5 dkh.

The most decline ive seen was at 30 min before the next dose ''early morning'' and the ALK was 7.2 DKH.
'this was because i was dosing not enough!!

So i then put this 0.3 DKH decline in my calculator and add the extra amount of alk to my bolus dose for that morning.

I dont know what the alk will be directly after dosing because i only took a measerment 60min after dosing.

I never stated that my ALK will NEVER drop, also i dont know the scientific reason why this is happing
I can only show you my dose and measurments

Surely you are not claiming you can add 2.5 dKH of bicarbonate in a bolus dose once every day, and yet at no time before the next dose does the alk ever detectably drop more than 0.3 dKH?


"The most decline ive seen was at 30 min before the next dose ''early morning'' and the ALK was 7.2 DKH.
'this was because i was dosing not enough!!"

If the alk rose to 7.5 dKH after dosing 2.5 dKh, that's fine.

But then 24 h later, BEFORE any more dosing, the alk is only 7.2 dKH, then where does the need for 2.5 dKH of dosing arise?

 

[Randy Holmes-Farley]

As I understand it, without having tried it, the idea is to strike a balance between photosynthesis starting early and driving up pH and growth, and the overdose of bicarb shifting the equilibrium between bicarb, carbonate and carbonic acid to a point where rather than alkalinity being used up, alkalinity stays fixed while the accumulated carbonic acid that was formed after dosing converts back and is used up instead

If that is the hypothesis, I don't see what it is explaining. The only way alkalinity can stay fixed to is prevent calcification (or dose it as it is used up, which many folks currently do).

Photosynthesis does not consume ANY alkalinity, but it does raise pH and thereby shifts the balance of the carbonate system to more carbonate, and less bicarbonate and less carbonic acid.

Calcification does consume alkalinity and lowers pH.

Dosing bicarbonate (or carbonate or hydroxide) instantly boosts alkalinity, and instantly changes pH based on what exactly you dosed. There is no lag in these processes beyond what is needed to mix it into the full tank volume.

 

[elysics]

Photosynthesis does not consume ANY alkalinity, but it does raise pH and thereby shifts the balance of the carbonate system to more carbonate, and less bicarbonate and less carbonic acid.

I think that's the idea, to initially produce a whole bunch of carbonic acid that doesn't count towards alkalinity, and then a rising pH over the course of the day shifts that balance to line up with consumption somehow while carbonic acid gets depleted

 

[Hypnotize]

No, same as you I didn't, and in case I will I will make sure to let you all know.

My point is this entire discussion here is based on a YouTube video and full of criticism. If it's productive cristisim, fair.

So what's in the infamous video?

A guy, who is reefing since over 35 years is saying that he had better growth with dosing Alk once a day. And that's it.

All he says in relation to FM products is that it works great with them.

He never claims KH will be stable during the day or whatever. He is giving his perspective on why it's better and that's all.

That’s not quite what happend since the company also Released a HTU with information or claims depending on who you believe.

 

[DutchReefer420]

Surely you are not claiming you can add 2.5 dKH of bicarbonate in a bolus dose once every day, and yet at no time during the day does the alk ever detectably drop more than 0.3 dKH?

yes i do at this moment!!
dont get me wrong, ive had bigger drops in DKH at first when starting this bolus methode
because i was under dosing it (not dosing enough DKH)
i worked my way up to the 2.5 DKH dose i run now

and im nor german nor a FM fan!!
i run my tanks as basic as possible and im normaly not the type who goes for some new gimmick!!
only because its free and i do not need to buy anything i tried it!

like i said i'm ready to give you all the facts i possibly can.
dosing amount and measurments with time and date

i just took a alk measurment and my alk is exactly the same as before me bolus dose this morning.

 

[Hypnotize]

Back on the hypothesized mechanism for any perceived benefit, I'll focus on this comment from the document I posted:

Using Fauna Marin Balling Light carbonate, it is possible to raise the pH substantially just before the start of the photoperiod by dosing the entire daily requirement in one dose, this is the Bolus. The timing is very important as there is a chemical re-balancing that can take between 10-30 minutes, this should be the delay between the Bolus dose and the start of the photoperiod.

and this picture:

Clearly, several things jump out.

1. As someone noted earlier, FM calls their product used here Fauna Marin Balling Light carbonate. It raises pH which is also consistent wit it being wholly or partly carbonate, not just bicarbonate. Bicarbonate will not raise the pH like that (yes, I have tried it).

2. FM claims the pH boost is important.

3. It is very plausible, IMO, that the pH is important. Most of us believe that many hard corals grow faster at higher pH, and if that growth mostly happens during the lit hours, then the higher pH during those hours immediately following the bolus dose may explain wholly or partly the improvements folks see.

4. If #3 is the explanation, then other means of attaining that pH may accomplish the same goals, without bolus dosing.

Fauna Marin clearly states that their Carbonate product only consists of Bicarbonate.
In the lifestream last night it was brought up that if you Randy claim Bicarbonate doesn’t raise you should go learn chemistry again.
The Carbonate product also claims if 500g of it mixed in 5L of RO 20ml of the solution raises the alk by 1 in a 100L aquarium.
I may be wrong but that would also indicate that it’s not possible to only be Bicarbonate or the product manuel is wrong.

 

[Randy Holmes-Farley]

I think that's the idea, to initially produce a whole bunch of carbonic acid that doesn't count towards alkalinity, and then a rising pH over the course of the day shifts that balance to line up with consumption somehow while carbonic acid gets depleted

But that doesn't happen. Photosynthesis and the pH change it causes has an exactly zero effect on alkalinity.

 

[Randy Holmes-Farley]

Fauna Marin clearly states that their Carbonate product only consists of Bicarbonate.
In the lifestream last night it was brought up that if you Randy claim Bicarbonate doesn’t raise you should go learn chemistry again.
The Carbonate product also claims if 500g of it mixed in 5L of RO 20ml of the solution raises the alk by 1 in a 100L aquarium.
I may be wrong but that would also indicate that it’s not possible to only be Bicarbonate or the product manuel is wrong.

lol

It is both exactly theoretically and experimentally accurate to say that bicarbonate dosing lowers pH a small amount when first dosed.

I've tried it, and published the results long ago, and anyone challenging me should simply try it themselves.

Everyone has baking soda in their home. It should not take more than 2 minutes to try if you have a pH meter.

Chemistry And The Aquarium: The Relationship Between Alkalinity And pH

Randy answers many questions in this complex relationship.

reefs.com

From it:

Alkalinity Supplements​

One of the most common issues that reefkeepers face involves supplementing alkalinity while maintaining a reasonable pH. Alkalinity supplements impact pH in a variety of ways. One of these ways is the immediate altering of the pH. Different alkalinity supplements have different immediate impacts on pH, as most reefkeepers are aware. This impact is why, for example, limewater needs to be added slowly to a tank but sodium bicarbonate does not.

For this discussion, let’s presume that we want to supplement the carbonate alkalinity of a reef tank. That is, in the end we want to increase the bicarbonate and carbonate levels in the tank. There are a variety of ways to achieve this end, and these different ways have different immediate impacts on pH. Three of these ways (and combinations thereof) are fairly common in reefkeeping. These ways are addition of bicarbonate, carbonate, and hydroxide. In a reef tank that is permitted to equilibrate its total CO2 levels with the atmosphere, these additions all end up with the same final pH. That is, it is only the amount of alkalinity added that determines the final pH, not the nature of the additive itself.

In the short term, however, the impact on pH is very different. To quantify this, 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

From this data it is clear to see the large increase in pH caused by the addition of hydroxide, and also the significant increase when using carbonate. Bicarbonate, on the other hand, shows the expected slight decrease in pH, but not nearly as much as is found with a strong acid of equal concentration. It is also clear that after sufficient time to equilibrate with atmospheric CO2, these differences disappear, and the pH is the same for all of the 0.5-meq/L alkalinity additions. This is an important result: in seawater in equilibrium with the atmosphere, for a given alkalinity there is a single pH that results, regardless of what was added to get to that alkalinity.

Here’s how to think of these additions. When these chemicals are added to the water, there is a change in the relative concentrations of carbonate and bicarbonate, and it is the ratio of these two ions that determines the pH.

 

[Randy Holmes-Farley]

This is also from it:

Bicarbonate Addition​

The addition of bicarbonate as an alkalinity supplement is rather different. In this case, the bicarbonate partially dissociates into carbonate and H+, and the tank experiences an increase in bicarbonate and carbonate, and a drop in pH.:

15. HCO3– → H+ + CO3—

Consequently, the immediate effect on pH is for it to drop. The drop is small because not much of the bicarbonate dissociates at normal tank pH, but enough does to drive the pH a bit lower (from 8.10 to 8.06 in the experiment above).

In the long term, however, the effect is different. Since a substantial amount of bicarbonate was added and the pH did not change much, the tank is now overloaded with bicarbonate with respect to what it would normally have in equilibrium with air. Some of the bicarbonate picks up a proton, becomes carbonic acid, and the pH rises as the CO2 is blown off to the atmosphere:

16. HCO3– + H+ → H2CO3 → CO2 + H2O

In the experiment above, this effect has caused the pH to rise from 8.06 to 8.33. So the long-term effect of bicarbonate addition (as it is for any addition to carbonate alkalinity) is to raise pH even though the short-term effect was to lower it.

 

[DutchReefer420]

I think that's the idea, to initially produce a whole bunch of carbonic acid that doesn't count towards alkalinity, and then a rising pH over the course of the day shifts that balance to line up with consumption somehow while carbonic acid gets depleted

this is exactly what FM claims is happening.
point 1

FM claims dosing would first drop your PH slightly after that it starts to rais again
also this is exactly what i am seeing!!

first a smal drop in PH there after a slow rais boosted by the extra light

 

[Garf]

I've tried it,

And me, it lowers pH a bit.

Feels like I've entered an alternative reality, perhaps a parallel universe with different physics.

 

[elysics]

But that doesn't happen. Photosynthesis and the pH change it causes has an exactly zero effect on alkalinity.

What I mean is, at the start of the day there is balance between a certain carbonate level and high carbonic acid, and at the end of the day there is balance between roughly the same carbonate level and little carbonic acid, and this transition, and the carbonate that is created by carbonic acid being converted back due to that change in balance, superimposed on the consumption by corals that happens at the same time, is supposed to produce a flat line as far as alkalinity is concerned

 

[DutchReefer420]

It is both exactly theoretically and experimentally accurate to say that bicarbonate dosing lowers pH a small amount when first dosed.

It is both exactly theoretically and experimentally accurate to say that bicarbonate dosing lowers pH a small amount when first dosed.

this is what FM claims!

first slight ph drop
there after ph goes up boosted by the extra light

 

[DutchReefer420]

What I mean is, at the start of the day there is balance between a certain carbonate level and high carbonic acid, and at the end of the day there is balance between roughly the same carbonate level and little carbonic acid, and this transition, and the carbonate that is created by carbonic acid being converted back due to that change in balance, superimposed on the consumption by corals that happens at the same time, is supposed to produce a flat line as far as alkalinity is concerned

sorry for me not being able to get this info in here
i think tis is exactly what FM was saying in there Video's

 

[Randy Holmes-Farley]

this is exactly what FM claims is happening.
point 1

FM claims dosing would first drop your PH slightly after that it starts to rais again
also this is exactly what i am seeing!!

first a smal drop in PH there after a slow rais boosted by the extra light

They show a sharp rise on dosing and a slow rise from photosynthesis, they specifically state this as well. See what I posted.