OP
OP
Lochnessholly
Aquarium Advice Activist
Make sure you link me if it does get its own thread. Would probably be good to know 
API Master Test Kit and green algae
- Thread starter Lochnessholly
- Start date
The friendliest place on the web for anyone with an interest in aquariums or fish keeping!
If you have answers, please help by responding to the unanswered posts.
If you have answers, please help by responding to the unanswered posts.
billsey420
Aquarium Advice Activist
- Joined
- Sep 9, 2012
- Messages
- 149
I think I miss read. I think he ment when you shake the vial. The harder he shook it the higher the reading
jlk
Aquarium Advice Addict
Ok, without getting technical, the API test measures NO3- or nitrate ion levels. The directions state other tests may only test for NO3-N and they will have a result that is 4.4x lower. The directions do NOT tell you to divide the API results by 4.4. The nitrate ion/NO3- is what is potentially toxic to fish and mammals alike in high concentrations. It binds with hemoglobin (red blood cells) and prevents them from acquiring oxygen. This is why the EPA has strict limits for allowable nitrate levels in public tap water because they can be fatal for infants, elderly and the immune suppressed (etc). Perhaps this is different for sw tanks but the API result for nitrate is what is in your fw tank (aside from the potential for error using it and how difficult it can be to decipher the chart/readings). No math necessary.
phishfriend
Aquarium Advice Addict
Everything I see refers the API saltwater test kit not the fresh...idk
OP
OP
Lochnessholly
Aquarium Advice Activist
The science behind what you said makes sense. I understand nitrate ions
So what is an acceptable reading?
So what is an acceptable reading?
billsey420
Aquarium Advice Activist
- Joined
- Sep 9, 2012
- Messages
- 149
This is out of my freshwater master test kit that I bought today
Bettafanatic
Aquarium Advice Addict
But you don't need the total nitrate. You only need the nitrate-nitrogen so why wouldn't you do a little extra math? It's just pressing a few buttons on a calculator. The total nitrate also includes nitrite-nitrogen and ammonia-nitrogen which you don't need to know.
jlk
Aquarium Advice Addict
I am going to try to get a better explanation on this for everyone but read the what the API states- it tests for the "nitrate ion (NO3-)". I think if API wanted you to divide your results by 4.4, they would state this explicitedly in their directions or their color chart would be completely different to reflect results divided by 4.4.
aqua_chem
Aquarium Advice Addict
Ok, I see where the problem is coming from.
This problem arises from using ppm as our units for measurement. Technically, ppm is 1 thing per million total things, which we transform into grams per million grams and eventually mg per liter for concentrations in water. While this is a practical measurement for certain applications, it fails in many others. The comes down to its dependence on the mass of what you're looking at. For comparison between chemicals, you need to use moles (the unit, not the rodent), which actually counts number of molecules rather than mass in solution. The issue is that 1 mole of nitrite weighs about 3.3x as much as one mole of ammonia, and nitrate weighs about 4.5x as much one mole of nitrate. This is due to the additional oxygens attached to the nitrogen.
Concept in action: you dose your aquarium with 4 ppm of ammonia. Over the coming weeks, the bacteria will convert it into a total of about 12 ppm nitrite and 18 ppm nitrate (but not all at once, obviously). If we were using moles, we would dose, say, 1 mmol of ammonia (or whatever it converts into, I'm not going to do unit conversions on vacation), which would turn into 1 mmol of nitrite and then 1 mmol of nitrate.
What does that mean to us? If you are going to compare nitrate levels to nitrite levels, or any two measurements using ppm, you need to keep in mind that these units are NOT equivalent. If you wanted to calculation total nitrogen, you would have to multiple each ppm by the total contribution that nitrogen makes to each component. That being said, there's really no benefit in doing that as it doesn't really give you a meaningful number. We spend that vast majority of our time comparing two measurements of the same unit, ie, ppm nitrate vs ppm nitrate, ppm ammonia vs ppm ammonia, etc. Dividing by 4.4 will give you total nitrate nitrogen concentration rather than nitrate concentration, but that doesn't really tell you anything that nitrate concentration wouldn't already tell us.
Any questions in this?
Edit disclaimer: most numbers were largely estimated because I haven't had my coffee yet. If anyone would like, I can get some more meaningful numbers in here.
This problem arises from using ppm as our units for measurement. Technically, ppm is 1 thing per million total things, which we transform into grams per million grams and eventually mg per liter for concentrations in water. While this is a practical measurement for certain applications, it fails in many others. The comes down to its dependence on the mass of what you're looking at. For comparison between chemicals, you need to use moles (the unit, not the rodent), which actually counts number of molecules rather than mass in solution. The issue is that 1 mole of nitrite weighs about 3.3x as much as one mole of ammonia, and nitrate weighs about 4.5x as much one mole of nitrate. This is due to the additional oxygens attached to the nitrogen.
Concept in action: you dose your aquarium with 4 ppm of ammonia. Over the coming weeks, the bacteria will convert it into a total of about 12 ppm nitrite and 18 ppm nitrate (but not all at once, obviously). If we were using moles, we would dose, say, 1 mmol of ammonia (or whatever it converts into, I'm not going to do unit conversions on vacation), which would turn into 1 mmol of nitrite and then 1 mmol of nitrate.
What does that mean to us? If you are going to compare nitrate levels to nitrite levels, or any two measurements using ppm, you need to keep in mind that these units are NOT equivalent. If you wanted to calculation total nitrogen, you would have to multiple each ppm by the total contribution that nitrogen makes to each component. That being said, there's really no benefit in doing that as it doesn't really give you a meaningful number. We spend that vast majority of our time comparing two measurements of the same unit, ie, ppm nitrate vs ppm nitrate, ppm ammonia vs ppm ammonia, etc. Dividing by 4.4 will give you total nitrate nitrogen concentration rather than nitrate concentration, but that doesn't really tell you anything that nitrate concentration wouldn't already tell us.
Any questions in this?
Edit disclaimer: most numbers were largely estimated because I haven't had my coffee yet. If anyone would like, I can get some more meaningful numbers in here.
Similar threads
