Dosing monosodium phosphate

[DarkSky]

Can someone check my math here? I'd like to raise my phosphates by 0.01ppm using monosodium phosphate (NaH2PO4). I have approximately 55g (208L) of volume.

NaH2PO4 = 119.98 g/mol, PO4 = ~95g/mol.

? mg/ 208L = 0.01ppm
208 * 0.01 = 2.08 mg

Is this correct? If so, I might mix 1L of RODI with 2g of NaH2PO4 and dose 1ml as needed.

Thank you in advance.

 

[Randy Holmes-Farley Verified Community Expert]

What you wrote seems correct, but doesn't give dosing amounts.

 

[DarkSky]

What you wrote seems correct, but doesn't give dosing amounts.

Thanks for responding, Randy. In the last section I mentioned I was going to dose 1ml of the prepared solution as needed to bring my levels up by 0.01ppm. I will adjust the levels once I figure out how much my tank is consuming daily.

 

[Randy Holmes-Farley Verified Community Expert]

OK, I misunderstood the "as needed" lol

The stock solution is about 1.6 g/L = 1,600 mg/L = 1.6 mg/mL

If you add 1 mL to 208 L, you'll boost phosphate by 1.6 mg/208 L = 0.008 mg/L

 

[HuskerTank]

Is 0.008 mg/L equivalent to 0.008 ppm?

 

[Randy Holmes-Farley Verified Community Expert]

Very close, yes.

1 mg/kg is 1 ppm. (since there are one million milligrams in one kilogram)

One liter of seawater weighs a bit more than 1 kg (say, 1.025 kilograms per liter).

So 0.008 mg/L = 0.008 mg/(1.025 kg) = 0.0078 mg/kg = ppm

 

[Citypetlanka]

What i heard monosodium phosphate reduce phosphate in marine tank? Am i correct?

 

[Citypetlanka]

What i heard monosodium phosphate reduce phosphate level in the tank! Am i correct? Can anyone explain what to add instead of GFO

 

[chipmunkofdoom2]

What i heard monosodium phosphate reduce phosphate level in the tank! Am i correct? Can anyone explain what to add instead of GFO

Monosodium phosphate does not lower phosphates, it raises them. You can use any number of things besides GFO for phosphate reduction (macro algae, lanthanum chloride or Phosphate RX, organic carbon, etc).