ppm=mg/L explained

[GoneFish'n]

I learned something today that I thought I would share. Of course everyone else already knew this.

When dealing with liquids (water in our case),

mg/L = ppm.

mg/L stands for milligrams per Liter, ppm stands for parts per million


Bear with me.

By definition, a Liter of water weighs 1 kg (1 kilogram or 1000 grams).

An 1 mg (1 milligram or 1/1000 of a gram)

Therefore 1 mg = 1/1,000,000 of a kg.

So, based on what we have learned: 1 mg/L = 1 mg/kg = 1 mg/million mg = ppm.

mg/L =ppm

Clear as mud? Well, it became clear to me when it was broken down like this.

Happy Aquaponicing!

Lynn

[nwestwood]

Because I don't think in metric, it took me awhile to figure that out as well. When you lay it out mathematically it makes sense. I have a log book and the very back page is nothing but conversion factors for metric to English. I also have my system measurements in both. Most of the scientific literature uses metric, but the US based suppliers and supplies are English.

Another handy fact is that:

1kg\1000 liters is 1 ppt (part per thousand), If you ever add salt to your system, this makes it easy. If you have a 1000 liter system, then it takes 1 kilogram of salt to get to 1 ppt. (we often salt our systems or quarantine tanks to 3-5ppt for fish health.)

There are 2.2lbs in a kilogram and there are 3.85 liters to a gallon.

[kellenw]

Good stuff. I was just explaining this to a client a few days ago. In this case I was explaining how much 3% H2O2 (hydrogen peroxide solution) he would need to add to a liter of water to use as an egg wash for tilapia eggs. I ended up telling him how many teaspoons he needed to add. FYI, 1 teaspoon equals 4.93 milliliters.