What is Reef Fusion Part 2 (Carbonate one) made from?

[Kerbash]

Hello,

Does anyone know what is the Reef fusion part 2 made from? Or how its made? It said its meq/L is 4400 thats wayyy more than the sodium carbonate solubility. I did manage to get close by boiling off the excess water, but it precipitated out of the solution slowly.

Did they use the sodium carbonate but just add acids to increase solubility?

Thanks

 

[taricha]

interesting question. I don't actually know if 4400 meq/L is possible. Here's my best guess (but there might be an error or two in the below).

normality of sodium carbonate is 2, and sodium bicarbonate is 1. So mixing with bicarbonate probably wouldn't help.
Looking up solubility of saturated sodium carbonate, I find 21.5 g/100mL = 215 g/L. at 106 g/mol that gives you 2.02 Molar, and since the normality = 2, that's 4.04 equivalents/L or 4040meq/L. Which is really close to the quoted 4400 meq/L.

 

[Randy Holmes-Farley]

Seachem rarely says what is in their products, and they make a number of unusual or incorrect claims, so I do not know if what they are saying about the potency is actually true.

That said, there are at least two ways once could attain this potency.

1. Mix sodium carbonate and sodium hydroxide
2. Add in other, unmentioned ions, such as potassium and sulfate.

Number 2 is an example of how ions can increase the solubility of other ions. This paper makes a good example of that:

https://pubs.acs.org/doi/10.1021/ed081p1644

The theory of activity versus concentration is important in industrial, environmental, and biochemistry. The increase in solubility of an electrolyte in a solution of a second electrolyte with no common ions compared with pure water is not an easy concept to grasp because it seems to be counterintuitive. The simple experiment described here illustrates this principle visually and dramatically. Students attempt to dissolve CaSO4•2H2O (gypsum) in pure water and in 0.25 M NaCl. The gypsum dissolves almost completely in the sodium chloride solution, but not in pure water. Students then measure the calcium concentrations in filtered aliquots of both solutions to quantify the solubility difference they observed. Students calculate mean activity coefficients using their measured concentrations and also from the Davies Equation, an extension of Debye–Hückel theory. The basic principle is there are ionic interactions between the solute ions and the solvent ions, which allow for more dissolution because only free ions enter into the expression for the solubility product equilibrium constant. From a simple mathematical point of view, in higher ionic strength solutions, activity coefficients for calcium and sulfate become smaller, and hence the concentrations must be larger to maintain a constant solubility product at equilibrium.

 

[Kerbash]

Seachem rarely says what is in their products, and they make a number of unusual or incorrect claims, so I do not know if what they are saying about the potency is actually true.

That said, there are at least two ways once could attain this potency.

1. Mix sodium carbonate and sodium hydroxide
2. Add in other, unmentioned ions, such as potassium and sulfate.

Number 2 is an example of how ions can increase the solubility of other ions. This paper makes a good example of that:

https://pubs.acs.org/doi/10.1021/ed081p1644

The theory of activity versus concentration is important in industrial, environmental, and biochemistry. The increase in solubility of an electrolyte in a solution of a second electrolyte with no common ions compared with pure water is not an easy concept to grasp because it seems to be counterintuitive. The simple experiment described here illustrates this principle visually and dramatically. Students attempt to dissolve CaSO4•2H2O (gypsum) in pure water and in 0.25 M NaCl. The gypsum dissolves almost completely in the sodium chloride solution, but not in pure water. Students then measure the calcium concentrations in filtered aliquots of both solutions to quantify the solubility difference they observed. Students calculate mean activity coefficients using their measured concentrations and also from the Davies Equation, an extension of Debye–Hückel theory. The basic principle is there are ionic interactions between the solute ions and the solvent ions, which allow for more dissolution because only free ions enter into the expression for the solubility product equilibrium constant. From a simple mathematical point of view, in higher ionic strength solutions, activity coefficients for calcium and sulfate become smaller, and hence the concentrations must be larger to maintain a constant solubility product at equilibrium.

Thanks for the reply, I think the first option is very likely right? Because when you add the product, white precipitate form, which points to a high pH? I guess ill give that a try.

 

[Kerbash]

interesting question. I don't actually know if 4400 meq/L is possible. Here's my best guess (but there might be an error or two in the below).

normality of sodium carbonate is 2, and sodium bicarbonate is 1. So mixing with bicarbonate probably wouldn't help.
Looking up solubility of saturated sodium carbonate, I find 21.5 g/100mL = 215 g/L. at 106 g/mol that gives you 2.02 Molar, and since the normality = 2, that's 4.04 equivalents/L or 4040meq/L. Which is really close to the quoted 4400 meq/L.

I actually got it to go around 4400 meq/L by creating a super saturated solution, which was fine for like a week or so, but it eventually formed a huge hunk of crystal at the bottom of the bottle.

 

[Reefer Matt]

I tried duplicating their recipe, but could never get the concentration that high without precipitation. My sps tanks have high alk demand, so I just pay for their product. The alk swung too much trying to use another product in my case.

 

[Randy Holmes-Farley]

Thanks for the reply, I think the first option is very likely right? Because when you add the product, white precipitate form, which points to a high pH? I guess ill give that a try.

That happens for carbonate too.

 

[Randy Holmes-Farley]

If someone wants to experiment, then we can suggest things like potassium sulfate or chloride to up the concentration that is stable.

 

[Kerbash]

I tried duplicating their recipe, but could never get the concentration that high without precipitation. My sps tanks have high alk demand, so I just pay for their product. The alk swung too much trying to use another product in my case.

Same, im too nervous to try anything else, but at the same time, Im going through a 500 mL bottle every week and a half and its really adding up.

That happens for carbonate too.

Sorry but can u explain why there is no white cloud when I add my NaCO3 solution too, it was around 3500-3700 meq/L? Is there a threshold where carbonate concentration start showing the white precipitant when added to the tank?

Also if you dont mind could you explain how does pH affect the solubility of NaCO3? I was talking to someone else today about your earlier comment "Mix sodium carbonate and sodium hydroxide". I was assuming that the NaCO3 solubility dont change but the effective alkalinity of the solution changed due to the raised pH. But they told me I was wrong and that higher pH causes NaCO3 to be more soluble? Because the high pH favors the formation of bicarbonate ions which causes more of the CO3 to dissociate? Is that correct?

Thank u!

 

[Randy Holmes-Farley]

What product are you adding?

I show what adding ESV B-ionic (bicarbonate) does here:

What is that Precipitate in My Reef Aquarium? by Randy Holmes-Farley - Reefkeeping.com

Figure 3. The transient cloud of magnesium hydroxide that forms when high pH additives are added. In this case, the alkalinity portion of B-ionic was added to a fairly still portion of one of my reef aquaria.​

 

[taricha]

Same, im too nervous to try anything else, but at the same time, Im going through a 500 mL bottle every week and a half and its really adding up.

If this is your concern, then you can do something like this -
Use a DIY sodium carbonate or bicarbonate solution - feel free to make it weaker (say half strength and dose 2x as much). There's no reason it needs to be the same concentration as the seachem product. The added volume is really small from a concentrated alk supplement. It's not like limewater.

 

[Reefer Matt]

If this is your concern, then you can do something like this -
Use a DIY sodium carbonate or bicarbonate solution - feel free to make it weaker (say half strength and dose 2x as much). There's no reason it needs to be the same concentration as the seachem product. The added volume is really small from a concentrated alk supplement. It's not like limewater.

I did that for a while myself. I calculated out the max concentration I could make with both sodium carbonate and bicarbonate. I found the cost of doing so to be close to just buying the Seachem product after the price went back down. I also noticed the diy solution would crystalize at the end of the dosing tube, where the Seachem product doesn’t. I wonder if they add some kind of stabilizer to the product or something?

 

[Randy Holmes-Farley]

I did that for a while myself. I calculated out the max concentration I could make with both sodium carbonate and bicarbonate. I found the cost of doing so to be close to just buying the Seachem product after the price went back down. I also noticed the diy solution would crystalize at the end of the dosing tube, where the Seachem product doesn’t. I wonder if they add some kind of stabilizer to the product or something?

I cannot imagine that the Seachem product is even close in price to using grocery store baking soda.

 

[Reefer Matt]

I cannot imagine that the Seachem product is even close in price to using grocery store baking soda.

Correct. I used the BRS soda ash and sodium bicarbonate.

 

[Randy Holmes-Farley]

If cost is a concern, I see no reason to use the BRS soda ash.