Trisodium Phosphate dosing math

[Chris Villalobos]

Trisodium Phosphate dosing math

I haven’t seen much talk about phosphate dosing using Trisodium Phosphate. Say I want to make a solution so that I can raise my phosphates 0.01 PPM by adding 1ml solution in a 40 gallon tank.

I’m using Na3PO4 99.9%

https://www.ebay.com/itm/321926386899


I was hoping someone can point me to the right formula.

 

[Big G]

I'm curious as well. Perhaps our reef chemist Randy can help @Randy Holmes-Farley

 

[aarbutina]

Trisodium Phosphate dosing math

I haven’t seen much talk about phosphate dosing using Trisodium Phosphate. Say I want to make a solution so that I can raise my phosphates 0.01 PPM by adding 1ml solution in a 40 gallon tank.

I’m using Na3PO4 99.9%

https://www.ebay.com/itm/321926386899


I was hoping someone can point me to the right formula.

Well i guess the question becomes is your requirement that the addition has to be exactly 1 mL.

Based on my math, if you add 1.88g of the Trisodium Phosphate to 1 liter of water, you can add 1.0003 mL to raise the phosphate level in your tank up to 0.01 ppm. I think adding 1 mL would be close enough.

This calculation was done using Randy's math from another post.

 

[aarbutina]

How did that ebay link get in there, I didn't add it... weird.

 

[Randy Holmes-Farley Verified Community Expert]

Trisodium phosphate is 58% phosphate by weight.

Adding 0.1 gram to 100 liters of tank water will boost phosphate by 0.6 ppm.

 

[Randy Holmes-Farley Verified Community Expert]

you can add 1.0003 mL to raise the phosphate level in your tank up to 0.01 ppm. I think adding 1 mL would be close enough.
.

lol

I hope so.

 

[Randy Holmes-Farley Verified Community Expert]

Based on my math, if you add 1.88g of the Trisodium Phosphate to 1 liter of water,

Just to clarify, that stock solution is 1090 ppm phosphate (1.88 x 0.58 g/L or 1.09 g/L or 1,090 mg/L).

Adding 1 ml per liter of tank water will boost phosphate by 1 mg/L.

Adding 1 mL per 100 L of tank water will boost phosphate by 0.01 ppm.

 

[aarbutina]

Trisodium phosphate is 58% phosphate by weight.

Adding 0.1 gram to 100 liters of tank water will boost phosphate by 0.6 ppm.

Shoot... you're right (of couse) Randy... Trisodium.... duh. I have just been looking at monosodium.

I'll amend my math. 2.6 grams in 1000 mL of water. would be a 1 ML addition right.

 

[aarbutina]

Just to clarify, that stock solution is 1090 ppm phosphate (1.88 x 0.58 g/L or 1.09 g/L or 1,090 mg/L).

Adding 1 ml per liter of tank water will boost phosphate by 1 mg/L.

Adding 1 mL per 100 L of tank water will boost phosphate by 0.01 ppm.

Again I wasn't totally clear there. Correct that was a stock solution. and I was calculating the addition to a 40 gallon tank.

 

[Chris Villalobos]

Trisodium phosphate is 58% phosphate by weight.

Adding 0.1 gram to 100 liters of tank water will boost phosphate by 0.6 ppm.

Thanks for the help everyone! I tried the math myself and I think I'm close to aarbutina's solution.


So if “Adding 0.1 gram to 100 liters of tank water will boost phosphate by 0.6 ppm”

Then 0.003 gram to 152 liters of tank water would boost phosphate by 0.01 ppm

If I made a solution where I dissolved 3 grams of TSP into 1 Liter of water I would have a solution that has 0.003 grams per ml.

I could then add 1 ml of said solution to my 152 liter tank and have phosphate raised by approximately 0.01ppm.

 

[Randy Holmes-Farley Verified Community Expert]

Again I wasn't totally clear there. Correct that was a stock solution. and I was calculating the addition to a 40 gallon tank.

FWIW, I wasn't meaning to say yours was wrong in any way, just generalizing it more.

 

[Randy Holmes-Farley Verified Community Expert]

Thanks for the help everyone! I tried the math myself and I think I'm close to aarbutina's solution.


So if “Adding 0.1 gram to 100 liters of tank water will boost phosphate by 0.6 ppm”

Then 0.003 gram to 152 liters of tank water would boost phosphate by 0.01 ppm

If I made a solution where I dissolved 3 grams of TSP into 1 Liter of water I would have a solution that has 0.003 grams per ml.

I could then add 1 ml of said solution to my 152 liter tank and have phosphate raised by approximately 0.01ppm.

Yes, or you could use the math I already posted.

1. add 1.88g of the Trisodium Phosphate to 1 liter of water,
2. Adding 1 mL per 100 L of tank water will boost phosphate by 0.01 ppm (so add 1.52 mL).

 

[aarbutina]

FWIW, I wasn't meaning to say yours was wrong in any way, just generalizing it more.

No worries Randy. I got what you were doing.

 

[Chris Villalobos]

Well my PO4 was so low that I couldn't trust my eyes reading the Red Sea test and the Hanna Phosphate checker readings were bouncing around at its limits so I had to get the Hanna ULR Phosphorus checker. First measurement came in at 5 ppb (0.015ppm PO4). Dosed one ml of the 0.003 gram/ml Trisodium Phosphate solution and the next test was 9 ppb (0.028 ppm PO4). I'm pretty impressed! Thanks for the help fellow reefers!

 

[aarbutina]

Nice! Glad to hear that the phosphorus checker is able to accurately dectect down that low. I actually just picked one up myself. Funny enough my phosphate levels are so low the meter read “0”.

Oh a side note, what’s the deal with it only coming with 6 reagent packets?!? Kinda lame!

 

[Chris Villalobos]

Nice! Glad to hear that the phosphorus checker is able to accurately dectect down that low. I actually just picked one up myself. Funny enough my phosphate levels are so low the meter read “0”.

Oh a side note, what’s the deal with it only coming with 6 reagent packets?!? Kinda lame!

Yeah I learned my lesson after the first Hanna Checker I bought. Luckily the reagent packs aren't too spendy.

 

[O'l Salty]

Formula for dosing phosphate and nitrate.

https://buddendo.home.xs4all.nl/aquarium/redfield_eng.htm

 

[KTTX]

Just to clarify, that stock solution is 1090 ppm phosphate (1.88 x 0.58 g/L or 1.09 g/L or 1,090 mg/L).

Adding 1 ml per liter of tank water will boost phosphate by 1 mg/L.

Adding 1 mL per 100 L of tank water will boost phosphate by 0.01 ppm.

@Randy Holmes-Farley, in the link is what I use, is your formula for any Trisodium?
Savogran 10621 Trisodium Phosphate (TSP) 1LB (16oz) https://www.amazon.com/dp/B0001GOGQW/ref=cm_sw_r_cp_apa_IUMZBbXMF51SZ

 

[Rich123]

I use a product to clean pools that has trisodium phosphate in it. I'm wondering if anyone can tell me how much would need to be added by volume to a 10,000 gallon swimming pool to raise the phosphate level by 1 ppb, 10 ppb, or 100 ppb. The info below is taken from the SDS sheet.

SECTION II-HARZADOUS INGREDIENTS/IDENTITY INFORMATION

SPECIFICE CHEMICAL IDENTITY; OSHA PEL

SODIUM METASILICATE PENTAHYDRATE 2mg/m3

TRISODIUM PHOSPHATE 10mg/M3

GLYCOL ETHER 50mg/m3

 

[Randy Holmes-Farley Verified Community Expert]

I use a product to clean pools that has trisodium phosphate in it. I'm wondering if anyone can tell me how much would need to be added by volume to a 10,000 gallon swimming pool to raise the phosphate level by 1 ppb, 10 ppb, or 100 ppb. The info below is taken from the SDS sheet.

SECTION II-HARZADOUS INGREDIENTS/IDENTITY INFORMATION

SPECIFICE CHEMICAL IDENTITY; OSHA PEL

SODIUM METASILICATE PENTAHYDRATE 2mg/m3

TRISODIUM PHOSPHATE 10mg/M3

GLYCOL ETHER 50mg/m3

That list is an OSHA tox limit, not anything about the product concentration.