DIY Amino Acid Dosing

[jrp1588]

I prepared a liter of solution with 100 millimolar of each amino acid and doses 10 ml of it every other day or so. Note that most of these amino acids (i.e. aromatic amino acids) have very low solubility in natural pH water, so I had to drop the pH to ~1 using HCl and heated the bottle to 70 Celsius. Even then I had some undissolved stuff. I am not sure if those were undissolved amino acids or impurities. If they were amino acids, some amino acids were below 100mM.

In hindsight, it may have been better to prepare the stock solution at with an amino acid ratio proportional to what is found in proteins. I may have unintentionally dosed carbon since some amino acids, like aromatics, were definitely in access due to their comparably low usage in proteins. Those were most likely broken down to make smaller more abundant proteins, and that pulled nitrate from water and reduced nitrate levels.

Interesting. How big of a tank was this being dosed on? How long did it make the skimmer overflow?

 

[Randy Holmes-Farley Verified Community Expert]

That's fair, I can start with a ballpark. Per liter of tank water?

Yes

 

[Randy Holmes-Farley Verified Community Expert]

@Randy Holmes-Farley do amino acids and vitamins in water at room temp decompose over time? I just found a 5gal container of Aquavitro Fuel that I forgot about in my storage unit. It’s been there for probably 3 or 4 years, and I was hoping I wouldn’t have to throw it away.

It looks and smells normal.

Amino acids will not fall apart in their own, but bacteria will thrive on them. The product may have an inhibitor in it.

 

[Randy Holmes-Farley Verified Community Expert]

Interesting about the skimmer. I wonder how the commercially prepared amino supps get around this. Do you still have your recipe by chance?

A few amino acids may be skimmed out, but not most of them.

 

[Randy Holmes-Farley Verified Community Expert]

All but histidine and lysine are also hydrophobic, and will make the skimmer go nuts.

I agree that some will be skimmed, but lysine is neither hydrophobic nor skimmable. It is extremely water soluble. One can make a solution that has more lysine than water.

 

[jrp1588]

Amino acids will not fall apart in their own, but bacteria will thrive on them. The product may have an inhibitor in it.

Thanks for your help. Any idea what a DIYer might add to increase shelf life? It sounds like the pH of the mixture has to be really low to even get them to dissolve. Would bacteria survive in this environment?

 

[Randy Holmes-Farley Verified Community Expert]

Thanks for your help. Any idea what a DIYer might add to increase shelf life? It sounds like the pH of the mixture has to be really low to even get them to dissolve. Would bacteria survive in this environment?

I’d be reluctant to drop pH too much since the solution will then deplete alk. You might add vinegar as the acid to prevent the alk issue. Maybe even dissolve the amino acids directly in vinegar.

 

[jrp1588]

I’d be reluctant to drop pH too much since the solution will then deplete alk. You might add vinegar as the acid to prevent the alk issue. Maybe even dissolve the amino acids directly in vinegar.

Okay, I have heard some mention of using vinegar, which sounds a lot less spicy than HCL. I wish I could just hand the bottom of Coral Amino to my chemical engineer brother and tell him "make this." Though, he formulates paint and industrial coatings for a living, and I'm assuming this falls under organic chem. lol

 

[Randy Holmes-Farley Verified Community Expert]

Okay, I have heard some mention of using vinegar, which sounds a lot less spicy than HCL. I wish I could just hand the bottom of Coral Amino to my chemical engineer brother and tell him "make this." Though, he formulates paint and industrial coatings for a living, and I'm assuming this falls under organic chem. lol

Yes, it’s mostly organic and some physical chemistry (my favorite). lol

 

[Tripod1404]

I agree that some will be skimmed, but lysine is neither hydrophobic nor skimmable. It is extremely water soluble. One can make a solution that has more lysine than water.

I was trying to say 8 amino acids on that list ,other than histidine and lysine, are hydrophobic and prone to being skimmed.

 

[Tripod1404]

Okay, I have heard some mention of using vinegar, which sounds a lot less spicy than HCL. I wish I could just hand the bottom of Coral Amino to my chemical engineer brother and tell him "make this." Though, he formulates paint and industrial coatings for a living, and I'm assuming this falls under organic chem. lol

They also dissolve in with high pH. The idea is to protonate or deprotonate them so that they have a molecular charge and dissolve better. Never tired this, but they may dissolve in saturated kalk solution.

I used HCl since I could drop the pH with a small amount of acid.

To be honest, you can probably dose them as powders as well.

 

[Randy Holmes-Farley Verified Community Expert]

I was trying to say 8 amino acids on that list ,other than histidine and lysine, are hydrophobic and prone to being skimmed.

Ah, ok, I see it that way now.

 

[knockout]

Hey don't stop!

 

[jrp1588]

Hey don't stop!

The unknowns were stacking up, and I started getting some nutrient issues, so I decided to shelve the idea for the moment. Surely it can't be too hard though. Kush has their own amino now, and he doesn't exactly strike me as a chemist.

 

[Randy Holmes-Farley Verified Community Expert]

I’m not sure the exact amino acids matter. I’d include aspartate and glutamate, but others may not matter which they are if the goal is an N source that is less likely to be used by green algae.