Experimental testing of Brightwell Boost pH +

[Dan_P]

Great, thanks for the additional experiment.

I am still looking for extraordinary data to justify the extraordinary vendor claims. So far, your world view still seems correct.

If you have any ideas for an experiment that might show how the vendors might have been fooled, let me know. I am out of details.

 

[jason2459]

I am still looking for extraordinary data to justify the extraordinary vendor claims. So far, your world view still seems correct.

If you have any ideas for an experiment that might show how the vendors might have been fooled, let me know. I am out of details.

Use an API kit. Low resolution works wonders.

 

[Dan_P]

Use an API kit. Low resolution works wonders.

I wonder if that is why it is on the market? The research team only had an API kit.

 

[taricha]

A 33x recommended dose showed a 0.02 meq/L increase, i.e., no effect. A 222x recommended dose showed a 0.34 meq/L increase.

Thanks. anecdotal observations are often just noise.

Did you have any more thoughts on the apparent disconnect between actual alkalinity and hanna-color alkalinity you saw with boost.

 

[rtparty]

I wonder if that is why it is on the market? The research team only had an API kit.

The research* department figured a large chunk of reefers used API and thus would never “see” the alkalinity increase.

*may or may not be real and may just be the marketing team aka bean counters. They had no idea the Chemistry Avengers would ever test their claims

 

[taricha]

Use an API kit. Low resolution works wonders.

heh. Because I'm such a fanboy of API reagents, I have to say you can totally get +-0.1 dKH resolution with API reagent.
Up the sample volume from 5ml to 15, so 1 drop is now worth 0.33dKH instead of 1 dKH, use a color card to match to the same particular green shade every time. And use a scale to mass the reagent bottle before and after, so you can do it by mass of titrant instead of drops - so you can do fractions of a drop to get the color just right.

 

[FUNGI]

This thread saved me $40 today....was going to buy Boost PH

 

[rtparty]

heh. Because I'm such a fanboy of API reagents, I have to say you can totally get +-0.1 dKH resolution with API reagent.
Up the sample volume from 5ml to 15, so 1 drop is now worth 0.33dKH instead of 1 dKH, use a color card to match to the same particular green shade every time. And use a scale to mass the reagent bottle before and after, so you can do it by mass of titrant instead of drops - so you can do fractions of a drop to get the color just right.

I would go with 100ml of sample. Then we can get like .02dkh. Cuz if you can’t tell me my alkalinity is 7.04 instead of 7.06dkh, I don’t want your test!!!

I made up numbers above. Don’t fact check the .02dkh

 

[Dan_P]

Thanks. anecdotal observations are often just noise.

Did you have any more thoughts on the apparent disconnect between actual alkalinity and hanna-color alkalinity you saw with boost.

I plan on a full data dump soon but the sneak preview is that my Checker reads 1.18x high between 2 and 4 meq/L. Thats roughly twice what you would expect from the methods accuracy of +/- 5 ppm +/- 5%. It is very precise though in measuring the relative change in alkalinity, well within the expected variation. I looked at the Hanna indicator absorption vs pH and alkalinity, both correlations looked OK, maybe a bit of non-linearity.

The disconnect seems to be all a Checker issue. My Checker had a systematic deviation becoming worse at higher alkalinities. I will generate some side by side comparisons of Hanna Checker and titrations with a pH meter, Red Sea and the much maligned API alkalinity test. I will also share the Checker study.

I continue to find no evidence for the claim that Boost pH+ does not raise alkalinity or as much as NaOH.

 

[Dan_P]

I plan on a full data dump soon but the sneak preview is that my Checker reads 1.18x high between 2 and 4 meq/L. Thats roughly twice what you would expect from the methods accuracy of +/- 5 ppm +/- 5%. It is very precise though in measuring the relative change in alkalinity, well within the expected variation. I looked at the Hanna indicator absorption vs pH and alkalinity, both correlations looked OK, maybe a bit of non-linearity.

The disconnect seems to be all a Checker issue. My Checker had a systematic deviation becoming worse at higher alkalinities. I will generate some side by side comparisons of Hanna Checker and titrations with a pH meter, Red Sea and the much maligned API alkalinity test. I will also share the Checker study.

I continue to find no evidence for the claim that Boost pH+ does not raise alkalinity or as much as NaOH.

Had some time today between laundry loads to pull together the data. First plot shows that while the Hanna method tracks alkalinity change very well, it reads high with newly opened reagent.

The second plot confirms that the method tracks alkalinity changes well and shows that the slope is a bit higher than expected. Error bars are the stated Hanna accuracy. The slope deviation in the first plot is larger than expected given the Hanna accuracy. I am still considering ways that I might be contributing to this error.

 

[taricha]

The disconnect seems to be all a Checker issue. My Checker had a systematic deviation becoming worse at higher alkalinities.

thanks for the effort on this bit that was only a loose end in my head.

 

[rtparty]

Disclaimer: all that stuff is well above my pay grade and may well be addressed in the graph and all the numbers.

With that said, Hanna has an accuracy of like .1dkh +-5% or something like that right? So the higher the alkalinity reading the larger the deviation? Meaning it wouldn’t be a perfectly linear transition and should have a slight curve?

Again, this is just for my learning and education on the topic and my sleep exhausted brain may be lagging today

 

[Dan_P]

Disclaimer: all that stuff is well above my pay grade and may well be addressed in the graph and all the numbers.

With that said, Hanna has an accuracy of like .1dkh +-5% or something like that right? So the higher the alkalinity reading the larger the deviation? Meaning it wouldn’t be a perfectly linear transition and should have a slight curve?

Again, this is just for my learning and education on the topic and my sleep exhausted brain may be lagging today

I hear you. All will be made clear soon.

I am still developing my understanding of the Hanna alkalinity method. I am currently studying how the method works. I will share what I learned and then we can debate “titration is/is not better than the Hanna Checker”

 

[Dan_P]

heh. Because I'm such a fanboy of API reagents, I have to say you can totally get +-0.1 dKH resolution with API reagent.
Up the sample volume from 5ml to 15, so 1 drop is now worth 0.33dKH instead of 1 dKH, use a color card to match to the same particular green shade every time. And use a scale to mass the reagent bottle before and after, so you can do it by mass of titrant instead of drops - so you can do fractions of a drop to get the color just right.

…or if the color change is suitable, titrating backwards will also help. By backwards I mean adding sample to a volume of titrant until the color changes.

For example, if 1mL of Red Sea titrant is used for a 10 mL sample, the alkalinity is 5 meq/L. If you titrate 1 mL of titrant with a different sample of aquarium water and hit the endpoint color change with more than 10 mL, then the alkalinity is lower and calculated by 5 meq/L * (10/sample volume added). This opens the door for tests using less reagent.

I will see how much the API test is improved with backward titrations.

 

[taricha]

nice @Dan_P that's quite clever and conserves reagent.
And it allows a really simple modification to get past the 1 drop = 1 dKH.
Do test like normal. The last drop goes past the endpoint to yellow, then add more tank water with a 1.00mL syringe to get back to the middle green correct endpoint. get a result like
9 drops for 5.14mL tank water = 9*(5.00/5.14) = 8.75 dKH.

edit: question on the full "backwards titration" .
Does anything weird happen when you add some aquarium water sample to the excess of strong acid because the pH is very low? Any sort of reaction occur to the tank water that would not in a normal titration with the pH being brought down from ~8 to ~4.5? Or should the ratio of acid to sample water be the same whether the acid is added gradually to the sample water or the smple water added gradually to the acid?

 

[Randy Holmes-Farley]

Do you guys know approximately what pH is attained in a Hanna alk test? The farther it is from the actual alk titration endpoint, the greater is the concern that odd effects can give false readings, such as very high or low pH, or excessively high borate as used to be present in Seachem salt mix.

 

[Dan_P]

nice @Dan_P that's quite clever and conserves reagent.
And it allows a really simple modification to get past the 1 drop = 1 dKH.
Do test like normal. The last drop goes past the endpoint to yellow, then add more tank water with a 1.00mL syringe to get back to the middle green correct endpoint. get a result like
9 drops for 5.14mL tank water = 9*(5.00/5.14) = 8.75 dKH.

edit: question on the full "backwards titration" .
Does anything weird happen when you add some aquarium water sample to the excess of strong acid because the pH is very low? Any sort of reaction occur to the tank water that would not in a normal titration with the pH being brought down from ~8 to ~4.5? Or should the ratio of acid to sample water be the same whether the acid is added gradually to the sample water or the smple water added gradually to the acid?

I can’t think of any reason why titration direction should matter except for the color transitions. For Red Sea, blue to yellow green when titrant is acid versus orange to blue-green when titrant is aquarium water. For me, the end point in the Red Sea kit is a little ambiguous in both directions, though I managed to get the correct results in both directions.

I haven’t attempted adding aquarium water to one drop of Red Sea titrant yet.

 

[Dan_P]

Do you guys know approximately what pH is attained in a Hanna alk test? The farther it is from the actual alk titration endpoint, the greater is the concern that odd effects can give false readings, such as very high or low pH, or excessively high borate as used to be present in Seachem salt mix.

Just finished studying how Hanna alkalinity method works. I will publish data soon. Here is a narrative.

The alkalinity reagent is a mixture of a dye and acid (strong acid). The dye changes color over a large pH range. This is not a titration indicator. The color intensity changes linearly with alkalinity, following the change in pH of the test solution. The dye absorbance at 606 nm changes when the reagent is added to aquarium water is linear for aquarium water containing 2-5 meq/L of alkalinity. I am not sure whether there is borate interference.

 

[Randy Holmes-Farley]

Just finished studying how Hanna alkalinity method works. I will publish data soon. Here is a narrative.

The alkalinity reagent is a mixture of a dye and acid (strong acid). The dye changes color over a large pH range. This is not a titration indicator. The color intensity changes linearly with alkalinity, following the change in pH of the test solution. The dye absorbance at 606 nm changes when the reagent is added to aquarium water is linear for aquarium water containing 2-5 meq/L of alkalinity. I am not sure whether there is borate interference.

Their method is likely similar to this method:

https://www.sciencedirect.com/science/article/abs/pii/096706379390149W

 

[Dan_P]

Their method is likely similar to this method:

https://www.sciencedirect.com/science/article/abs/pii/096706379390149W

Looks like it.