Trisodium Phosphate dosing math

[Rich123]

You're right. Thanks. After checking with the manufacturer, they're not using trisodium phoshate. They're using sodium tripolyphosphate and there's 50 pounds in 275 gallons. Are you able to do that math?

 

[Reefahholic]

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).

Trisodium phosphate is 58% phosphate by weight.

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

 

[Rich123]

Where can find what weight percentage of phosphate is in STPP and do I need that to get to grams per liter?

 

[Rich123]

Does anyone know how to calculate how many gallons of liquid are needed to raise the phosphate level 1 ppb in 10,000 gallons of water assuming the liquid that you're adding contains a mixture of 50 pounds of sodium tripolyphosphate in 275 gallons of water?

 

[Barks]

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).

Hi randy,
lim just about to raise my phosphate from zero, can I go straight to 0.05 or should it be done gradually?
many thanks

 

[KTTX]

IMO I wouldn't do more than .01 daily or every other day...gradually is best.

Hi randy,
lim just about to raise my phosphate from zero, can I go straight to 0.05 or should it be done gradually?
many thanks

 

[Randy Holmes-Farley Verified Community Expert]

Hi randy,
lim just about to raise my phosphate from zero, can I go straight to 0.05 or should it be done gradually?
many thanks

It won’t go up as fast as you add it. Much will bind to rock and sand. 0.05 ppm seems fine to add and see what happens.

 

[kevin_e]

I don't have a scale. How can I convert TSP from grams to tsp to produce a dosing fluid?

 

[Randy Holmes-Farley Verified Community Expert]

I don't have a scale. How can I convert TSP from grams to tsp to produce a dosing fluid?

As an approximation, 1 mL bulk powder weighs about 1 g. That's close enough for our purposes here.

 

[kevin_e]

As an approximation, 1 mL bulk powder weighs about 1 g. That's close enough for our purposes here.

Thanks that appears to be close enough. I used a bulk density of 950 kg/cubic meter and a weight of 1.88 grams. Did some conversations and used the formula p=m/v, and ended up with a value of 0.40 tsp. Using the approximation I calculated 0.38 tsp. So, like you said, for our purposes, the approximation is close enough and conservative.

 

[kevin_e]

As an approximation, 1 mL bulk powder weighs about 1 g. That's close enough for our purposes here.

I have added 0.16 ppm over the course of the week and still read "0" on my Hanna ULR after 3 separate tests 2-12 hours after dosing. Are biological and sorption processes happening that are stripping the phosphates so quickly? I have seen no uptick in algae growth anywhere. besides the little bit of transitional algae I have after treating for Golden algae.

 

[Randy Holmes-Farley Verified Community Expert]

I have added 0.16 ppm over the course of the week and still read "0" on my Hanna ULR after 3 separate tests 2-12 hours after dosing. Are biological and sorption processes happening that are stripping the phosphates so quickly?

Yes, that's pretty much expected.

 

[kevin_e]

Yes, that's pretty much expected.

Gotcha. Should I continue dosing until I register my desired amount?

 

[titus'reef]

Hello reefers!
Is Savogran 10621 Trisodium Phosphate (TSP) 1LB (16oz) what you guys are using? If not what are you using? I’m trying to raise my phosphate in my reef tank.

 

[Randy Holmes-Farley Verified Community Expert]

I'd get food grade sodium phosphate. Amazon carries it.

Like this one:

 

[titus'reef]

I'd get food grade sodium phosphate. Amazon carries it.

Like this one:

Thank you for the clarification. I’ll order that one. Will this have the same ratios for dosing as described in previous posts?

 

[Maximitsurugi]

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.

I know the post is old Randy but does trisodium phosphate solution lose potency over time? Or is my hanna having a problem reading it? My reagents are good until 2022.

I mixed some the other day and it seemed to do the trick but after a few months i only ever read 0 on my hanna and when i put a little in the vial directly it doesnt turn bkue like it used to. This led me to sprinkle a tiny bit of TSP crystal itslef into the vial and BOOM blue.

Has my mixture expired? Lol

 

[Randy Holmes-Farley Verified Community Expert]

I know the post is old Randy but does trisodium phosphate solution lose potency over time? Or is my hanna having a problem reading it? My reagents are good until 2022.

I mixed some the other day and it seemed to do the trick but after a few months i only ever read 0 on my hanna and when i put a little in the vial directly it doesnt turn bkue like it used to. This led me to sprinkle a tiny bit of TSP crystal itslef into the vial and BOOM blue.

Has my mixture expired? Lol

If it is the only thing in the solution, it won't go bad.

Perhaps demand in the tank has risen.

 

[Maximitsurugi]

If it is the only think in the solution, it won't go bad.

Perhaps demand in the tank has risen.

Its actually the solution tyat seemed to getvweaker but i just tossed ot out and mixed some up fresh. Lol

 

[tinhorse]

Will any tsp work or....? I have a box of this as it was handy to buy but when I mix up a solution of it and add lots to a test bucket of water my phosphate reading is still zero. I test my tap water and it reads at 0.03. Is this normal or should I toss this tsp and search for another?