HELP! Converting Phosphrous ppm to umol/L.

[Anonymous]

Can anyone link me to a site that has the conversion ration of ppm to umol/l?

Thanks,
Brian

 

[Cabreradavid]

I don't know of sites offering this info, but if you simply want the equation needed it is down below (if you already knew the equation and were looking for a quick way to do it, just ignore);


First, you obviously need the concentration of your solute in ppm (mg/L), and the molar mass of he solute ( for example, Salt (NaCl) is 58.44 g/mol). I am not sure if you are talking phosphate or elemental phosphorus, so I'll leave that to you. Anyways, here is the equation, in a step by step format so you follow my reasoning:

Start with ppm, let's say 35ppm NaCl which is also 35mg/L


35mg/l (NaCl) X 1g/1000mg ( to get to grams) X 1 mol/58.44 g NaCl

X 1 umol/ 1E-6 mol =599 umol/L .

I hope that makes sense. Again, If you knew the conversion and were looking for a calculator, sorry for being preseumptuous.

 

[liquid]

Here's how you do it:

1 ppm = 1 mg/L

To convert from ppm to µmol/L do the following:

1 g/mol = 1 mg/mmol

µmol/L = [ (mg/L) / (mg/mmol) ] * 1000 µmol/mmol

While I'm thinking about it, here's a *killer* convert program that's free for download. I use it daily at work:

http://www.joshmadison.com/software/con ... wnload.asp

FYI: to make the "µ" symbol, type the number 230 while holding down the ALT key.

hth

Shane

 

[Anonymous]

Thanks guys. I was trying to avoid thinking. I just burned my brain out last week defending my thesis and was looking for a shortcut.

I think I will try the converter, then resort to the math if that doesn't work.

Thanks again.

I'm going from 0.003ppm Phosphate to umol/L . Count on Instant Ocean to not specify which form of phosphate they were measuring.

 

[Cabreradavid]

Oh geez your thesis,

I completely understand your brain being fried. Mine sure was after my thesis. But knowing it is over with sure is nice.

 

[Anonymous]

0.03ppm of PO4 is about .06uM concentration.

That is what Aqua Craft tested the Instant Ocean to contain.

Lapointe,1997 and Bell, 1992 propose that levels of .1uM PO4 are enough to cause macroalgae to dominate a coral reef and can lead to crystal formation poisoning (Simkiss, 1964).

Too high if you ask me!

That means even if we change our water frequently, we must really work to keep phosphate levels low and below this proposed threshold limit.