conversion factors?

[JBrown]

How would one go about taking water quality perameters (PO4-P/L) and converting them from ugm/L to ppm?

[thackray]

Do you mean milligram/liter (mg/L) or microgram/liter (ug/L)?

1 mg/L = 1 PPM (One Part by weight per Million)

1 ug/L = 1 PPB (One Part by weight per Billion)

The exact relationship depends on the density of water but for any practicle need, use the above relationships.

And

1mg/L = 1000 ug/L

Phil

[Randy Holmes-Farley]

Thanks, Phil.

[Fastmarc]

Not sure if this would matter much as I do not know how precise you need to be or if it is even correct, but I saw a reference that stated the following:
1 ppm = 1.03 mg/L
1 mg/L = 0.98 ppm

[Randy Holmes-Farley]

Yes, that is because ppm = mg/kg, but 1 L = 1.026 kg, or thereabouts depending on the density of the water.

[JBrown]

thanks for the help guys

[Randy Holmes-Farley]

You're welcome.

Happy Reefing.

[Boomer]

Just say this and have to add something that my have been missed

ppm x density = mg / l

and be carerful with that phosphate value when comparing. It is NOT PO4 but PO4-P. Most kits measure PO4 as PO4 and not PO4-P. In reef tanks we speak in terms of PO4, not PO4-P

1 mg / l or 1 ppm PO4-P = 2.65 ppm or mg/ l PO4.

So, if your kit says 1 ppm Phosphate we are going to say it is really 2.64 ppm phosphate

[Randy Holmes-Farley]

So, if your kit says 1 ppm Phosphate we are going to say it is really 2.64 ppm phosphate

I assume that you meant to write:

"So, if your kit says 1 ppm phosphate-P, we are going to say it is really 2.64 ppm phosphate"

[Boomer]

Yes