Could I Get a Quick Double Check on Combo NO3+PO4 Stock Solution?

naterealbig · Sep 18, 2023

Hello! I am trying to make a single stock solution that will raise my 135 gallon system's nitrates to 5.0 ppm and phosphate to 0.07 ppm with a 10 ml stock solution dose.

For my stock solution, I am adding:

1. Trisodium Phosphate (Na3PO4 [LOUDWOLF-stated 99.9% pure])
2. Sodium Nitrate (NaNO3 [MODERNEST PANTRY-stated 100.0% pure])

Stock Solution Calculation:

Na3PO4 (** 58% PO4 per Na3PO4 by weight noted in previous thread**)
So, 0.07 ppm = (0.07 mg PO4 / L salt water) * (1 mg Na3PO4 / 0.58 mg PO4) * ( 3.785 L / gal ) * (135 gal salt water) = 61.7 mg Na3PO4 total dose needed
So, (61.7 mg / 10 ml fresh water) * (100) = 6,170 mg / 1000ml = 6.2 g / L to make stock solution

NaNO3 (** 73% NO3 per NaNO3 by weight noted in previous thread**)
So, 5.0 ppm = (5.0 mg NO3 / 1000 ml salt water) * (1 NO3PO4 / 0.73 NO3) * (3.785 L / gal) * (135 gal) = 3,500 mg Na3PO4 total dose needed
So, (3,500 mg / 10 ml) * (100) = (350,000 mg / 1000 ml) = 350 g NaNO3 / l to make stock solution

By-the-by: any issue with mixing the NaNO3 and Na3PO4 together in a single 1 liter stock solution?

Thank you!!

KStatefan · Sep 18, 2023

naterealbig said:
Hello! I am trying to make a single stock solution that will raise my 135 gallon system's nitrates to 5.0 ppm and phosphate to 0.07 ppm with a 10 ml stock solution dose.

For my stock solution, I am adding:

1. Trisodium Phosphate (Na3PO4 [LOUDWOLF-stated 99.9% pure])
2. Sodium Nitrate (NaNO3 [MODERNEST PANTRY-stated 100.0% pure])

Stock Solution Calculation:

Na3PO4 (** 58% PO4 per Na3PO4 by weight noted in previous thread**)
So, 0.07 ppm = (0.07 mg PO4 / L salt water) * (1 mg Na3PO4 / 0.58 mg PO4) * ( 3.785 L / gal ) * (135 gal salt water) = 61.7 mg Na3PO4 total dose needed
So, (61.7 mg / 10 ml fresh water) * (100) = 6,170 mg / 1000ml = 6.2 g / L to make stock solution

NaNO3 (** 73% NO3 per NaNO3 by weight noted in previous thread**)
So, 5.0 ppm = (5.0 mg NO3 / 1000 ml salt water) * (1 NO3PO4 / 0.73 NO3) * (3.785 L / gal) * (135 gal) = 3,500 mg Na3PO4 total dose needed
So, (3,500 mg / 10 ml) * (100) = (350,000 mg / 1000 ml) = 350 g NaNO3 / l to make stock solution

By-the-by: any issue with mixing the NaNO3 and Na3PO4 together in a single 1 liter stock solution?

Thank you!!

I have no idea if you can mix them. I would not since what i needed to dose changed often.

The math looks correct and matches what I have in my spreadsheet.

naterealbig · Sep 18, 2023

KStatefan said:
I have no idea if you can mix them. I would not since what i needed to dose changed often.

The math looks correct and matches what I have in my spreadsheet.

Thank you!

I actually stole your NaNO3 mass calculation for my post - I'm sorry for not giving you credit!

This is very helpful.

By-the-by - I love your spreadsheet. If you really wanted to, I wouldn't mind if you emailed it to me

I'll send my email in a PM. No pressure though.

Best Regards - Nathan