NO3 vs NO-3 Nitrate Test

[dehaanj]

I have two nitrate test kits... one indicates it test for NO3 which I get a reading of somewhere between 0 - 2.5 ppm, the other test indicates it's for NO-3 (high dash) which I get a reading of 20 ppm. Can someone explain the difference between these test? And which test one do I want to test for... NO3 or NO-3? Any assistance is greatly appreciated!

 

[wrightme43]

What are the brand names? That will help alot. Steve

 

[dehaanj]

Steve,

The NO3 is a Red Sea test kit and the NO-3 is a Saltwater Master kit.

 

[dehaanj]

The Red Sea kit has the following note:

It is not always clear whether a Nitrate test measures the NO3 Ions or the NO-3 Nitrogen (NO3-N) This test gives you the amount of NO3 Ions in ppm.

 

[wrightme43]

Well I have had the red sea kit, and the Aquarium Pharmecuitcals Master Kit. The red sea seemed to more accurate, to a point. I know they cost more I now use Salifert kits. They have saved me much scratching my head and running around trying to figure out what I need to do. It has turned out that a Nitrate reading of what looks to be 10ppm on AP master kit is a reading of no measurable nitrate on Salifert. Phosphate on a seatest kit that goes down to .2ppm would always show something hard to tell and then when using the salifert it has a reading of no measurable change. On Calcium it was always a guess, and now its dead on. Kh the same thing. I dont work for Salifert or anything. I just like them alot. I know this didnt answer your question. I dont really know the answer. Steve

 

[dehaanj]

Thank you for looking into it and the reply! And yes that AP kit does indicate a higher level of nitrate. I might pick up a Salifert kit to see what I get with it.... and/or take a water sample to the LFS to see what they get.

I've been using the AP kit and have had readings as high as 40. Change from CC to about 4" of sand a couple of weeks ago.... to lower Nitrate, and now getting 20 ppm today with the AP kit. I purchased the Red Sea kit last weekend, and used it for the first time this morning, and the reading of less than 2.5 ppm surprised me! Well thanks again, I'm going to try a Salifert kit and my LFS. Should be interesting.

 

[Boomer]

NO3 vs NO-3 Nitrate Test

They are the same kinda' It is like dKH vs meq or C vs F or cm vs inch.


In the NO3-N you are only measuring the weight of the N. In the NO3 you are measuring the weight of the N and 3O

1 mol of N = 14

1 mol of O = 16 and there are 3 O

so, it is 14 vs 62 (14 +16 +16 16)

62 /14 = 4.4 so,

1 ppm NO3-N = 4.4 ppm NO3

The std is NO3-N and is what most test kits are and what most values given are. The chemical world only cares about the N content. If you were doing a EPA chemcial report and reported it in NO3, you would get your report back and would be told to change and don't do that again